feat: minor fixes + code cleanup

34 files changed, 1384 insertions, 952 deletions

diff --git a/src/about.cpp b/src/about.cpp
index 81657e8..3c7f826 100644
--- a/src/about.cpp
+++ b/src/about.cpp
@@ -17,7 +17,7 @@ About::About(QWidget *parent) : QWidget(parent), ui(new Ui::About) {
   appAuthorEmail = "keshavnrj@gmail.com";
   appAuthorLink = "http://ktechpit.com";
   donateLink = "https://paypal.me/keshavnrj/5";
-  moreAppsLink = "https://snapcraft.io/search?q=keshavnrj";
+  moreAppsLink = "https://snapcraft.io/publisher/keshavnrj";
 
   appSourceCodeLink = "https://github.com/keshavbhatt/whatsie";
   appRateLink = "snap://whatsie";
@@ -42,7 +42,7 @@ About::About(QWidget *parent) : QWidget(parent), ui(new Ui::About) {
 
   ui->version->setText("Version: " + QApplication::applicationVersion());
 
-  ui->debugInfoText->setHtml(utils::appDebugInfo());
+  ui->debugInfoText->setHtml(Utils::appDebugInfo());
 
   ui->debugInfoText->hide();
 
@@ -92,14 +92,9 @@ void About::on_debugInfoButton_clicked() {
   }
 }
 
-void About::keyPressEvent(QKeyEvent *e)
-{
-   if (e->key() == Qt::Key_Escape)
-      this->close();
+void About::keyPressEvent(QKeyEvent *e) {
+  if (e->key() == Qt::Key_Escape)
+    this->close();
 
-   QWidget::keyPressEvent(e);
-}
-
-void About::on_donate_2_clicked() {
-  QDesktopServices::openUrl(QUrl("https://opencollective.com/whatsie"));
+  QWidget::keyPressEvent(e);
 }
diff --git a/src/about.h b/src/about.h
index cd9e978..fc946e6 100644
--- a/src/about.h
+++ b/src/about.h
@@ -1,36 +1,31 @@
 #ifndef ABOUT_H
 #define ABOUT_H
 
-#include <QWidget>
 #include <QKeyEvent>
+#include <QWidget>
 
 namespace Ui {
 class About;
 }
 
-class About : public QWidget
-{
-    Q_OBJECT
+class About : public QWidget {
+  Q_OBJECT
 
 public:
-    explicit About(QWidget *parent = nullptr);
-    ~About();
+  explicit About(QWidget *parent = nullptr);
+  ~About();
 
-protected slots:
-    void keyPressEvent(QKeyEvent *e);
+protected:
+  void keyPressEvent(QKeyEvent *e) override;
 private slots:
-    void on_debugInfoButton_clicked();
-
-    void on_donate_2_clicked();
+  void on_debugInfoButton_clicked();
 
 private:
-    Ui::About *ui;
+  Ui::About *ui;
 
-    QString appName, appDescription,
-            appSourceCodeLink, appAuthorLink,
-            appAuthorName, appAuthorEmail,
-            donateLink,moreAppsLink, appRateLink;
-    bool isOpenSource;
+  QString appName, appDescription, appSourceCodeLink, appAuthorLink,
+      appAuthorName, appAuthorEmail, donateLink, moreAppsLink, appRateLink;
+  bool isOpenSource;
 };
 
 #endif // ABOUT_H
diff --git a/src/about.ui b/src/about.ui
index b828eb2..9bad693 100644
--- a/src/about.ui
+++ b/src/about.ui
@@ -7,7 +7,7 @@
     <x>0</x>
     <y>0</y>
     <width>522</width>
-    <height>486</height>
+    <height>487</height>
    </rect>
   </property>
   <property name="windowTitle">
@@ -173,13 +173,6 @@ p, li { white-space: pre-wrap; }
             </widget>
            </item>
            <item>
-            <widget class="QPushButton" name="donate_2">
-             <property name="text">
-              <string>Donate OpenCollective</string>
-             </property>
-            </widget>
-           </item>
-           <item>
             <widget class="QPushButton" name="rate">
              <property name="text">
               <string>Rate in Store</string>
diff --git a/src/autolockeventfilter.h b/src/autolockeventfilter.h
index 9c35c45..c061fe8 100644
--- a/src/autolockeventfilter.h
+++ b/src/autolockeventfilter.h
@@ -19,7 +19,7 @@ public:
 
   ~AutoLockEventFilter() {
     autoLockTimer->stop();
-    autoLockTimer->deleteLater();
+    delete autoLockTimer;
   }
 
 signals:
@@ -39,18 +39,13 @@ public slots:
 
 protected:
   bool eventFilter(QObject *obj, QEvent *ev) {
-    if (ev->type() == QEvent::KeyPress
-            || ev->type() == QEvent::MouseMove
-            || ev->type() == QEvent::Wheel
-            || ev->type() == QEvent::TouchUpdate
-            || ev->type() == QEvent::MouseButtonRelease
-            || ev->type() == QEvent::MouseButtonPress
-            || ev->type() == QEvent::MouseButtonDblClick
-            || ev->type() == QEvent::Gesture
-            || ev->type() == QEvent::FocusIn
-            || ev->type() == QEvent::FocusOut
-            || ev->type() == QEvent::Enter
-            ) {
+    if (ev->type() == QEvent::KeyPress || ev->type() == QEvent::MouseMove ||
+        ev->type() == QEvent::Wheel || ev->type() == QEvent::TouchUpdate ||
+        ev->type() == QEvent::MouseButtonRelease ||
+        ev->type() == QEvent::MouseButtonPress ||
+        ev->type() == QEvent::MouseButtonDblClick ||
+        ev->type() == QEvent::Gesture || ev->type() == QEvent::FocusIn ||
+        ev->type() == QEvent::FocusOut || ev->type() == QEvent::Enter) {
       resetTimer();
     }
     return QObject::eventFilter(obj, ev);
diff --git a/src/automatictheme.cpp b/src/automatictheme.cpp
index 3cf33c8..9b1f3e7 100644
--- a/src/automatictheme.cpp
+++ b/src/automatictheme.cpp
@@ -2,26 +2,27 @@
 #include "ui_automatictheme.h"
 
 #include "sunclock.hpp"
-#include <QMessageBox>
 
 AutomaticTheme::AutomaticTheme(QWidget *parent)
     : QWidget(parent), ui(new Ui::AutomaticTheme) {
   ui->setupUi(this);
   ui->refresh->setEnabled(false);
 
-  sunrise.setSecsSinceEpoch(settings.value("sunrise").toLongLong());
-  sunset.setSecsSinceEpoch(settings.value("sunset").toLongLong());
+  m_sunrise.setSecsSinceEpoch(
+      SettingsManager::instance().settings().value("sunrise").toLongLong());
+  m_sunset.setSecsSinceEpoch(
+      SettingsManager::instance().settings().value("sunset").toLongLong());
 
-  ui->sunrise->setTime(sunrise.time());
-  ui->sunset->setTime(sunset.time());
+  ui->sunrise->setTime(m_sunrise.time());
+  ui->sunset->setTime(m_sunset.time());
 
   QTimeZone zone = QTimeZone::systemTimeZone();
   QDateTime dt = QDateTime::currentDateTime();
 
   if (zone.isValid()) {
-    hour_offset = (double)zone.standardTimeOffset(dt) / (double)3600;
+    m_hourOffset = (double)zone.standardTimeOffset(dt) / (double)3600;
   } else {
-    settings.setValue("automaticTheme", false);
+    SettingsManager::instance().settings().setValue("automaticTheme", false);
     QMessageBox::critical(
         this, "Error",
         "Unable to get system TimeZone information.\n\nAutomatic theme "
@@ -29,34 +30,34 @@ AutomaticTheme::AutomaticTheme(QWidget *parent)
     return;
   }
 
-  gPosInfoSrc = QGeoPositionInfoSource::createDefaultSource(this);
+  m_gPosInfoSrc = QGeoPositionInfoSource::createDefaultSource(this);
 
-  if (gPosInfoSrc) // sudo apt install geoclue-2.0
+  if (m_gPosInfoSrc) // sudo apt install geoclue-2.0
   {
     ui->refresh->setEnabled(true);
-    connect(gPosInfoSrc, &QGeoPositionInfoSource::positionUpdated,
+    connect(m_gPosInfoSrc, &QGeoPositionInfoSource::positionUpdated, this,
             [=](const QGeoPositionInfo &update) {
               QGeoCoordinate cor = update.coordinate();
               if (cor.isValid()) {
-                this->lon = cor.longitude();
-                this->lat = cor.latitude();
+                this->m_longitude = cor.longitude();
+                this->m_latitube = cor.latitude();
                 ui->refresh->setEnabled(true);
-                gPosInfoSrc->stopUpdates();
+                m_gPosInfoSrc->stopUpdates();
               } else {
                 ui->refresh->setEnabled(false);
               }
             });
-    connect(gPosInfoSrc, &QGeoPositionInfoSource::updateTimeout, [=]() {
-      if (!settings.value("sunrise").isValid() ||
-          !settings.value("sunset").isValid()) {
+    connect(m_gPosInfoSrc, &QGeoPositionInfoSource::updateTimeout, this, [=]() {
+      if (!SettingsManager::instance().settings().value("sunrise").isValid() ||
+          !SettingsManager::instance().settings().value("sunset").isValid()) {
         if (ui->refresh->isEnabled())
           ui->refresh->click();
       }
     });
-    gPosInfoSrc->startUpdates();
+    m_gPosInfoSrc->startUpdates();
   } else {
     ui->refresh->setEnabled(false);
-    settings.setValue("automaticTheme", false);
+    SettingsManager::instance().settings().setValue("automaticTheme", false);
     QMessageBox::critical(
         this, "Error",
         "Unable to initialize QGeoPositionInfoSource.\n\nAutomatic theme "
@@ -66,52 +67,56 @@ AutomaticTheme::AutomaticTheme(QWidget *parent)
 }
 
 AutomaticTheme::~AutomaticTheme() {
-  gPosInfoSrc->disconnect();
-  gPosInfoSrc->deleteLater();
+  m_gPosInfoSrc->disconnect();
+  m_gPosInfoSrc->deleteLater();
   delete ui;
 }
 
 void AutomaticTheme::on_refresh_clicked() {
-  QGeoCoordinate geoCor = QGeoCoordinate(this->lat, this->lon);
+  QGeoCoordinate geoCor = QGeoCoordinate(this->m_latitube, this->m_longitude);
   if (geoCor.isValid()) {
-    Sunclock sun(this->lat, this->lon, this->hour_offset);
-    sunrise.setSecsSinceEpoch(
-        sun.sunrise(QDateTime::currentDateTime().toTime_t()));
-    sunset.setSecsSinceEpoch(
-        sun.sunset(QDateTime::currentDateTime().toTime_t()));
+    Sunclock sun(this->m_latitube, this->m_longitude, this->m_hourOffset);
+    m_sunrise.setSecsSinceEpoch(
+        sun.sunrise(QDateTime::currentDateTimeUtc().toTime_t()));
+    m_sunset.setSecsSinceEpoch(
+        sun.sunset(QDateTime::currentDateTimeUtc().toTime_t()));
 
-    ui->sunrise->setTime(sunrise.time());
-    ui->sunset->setTime(sunset.time());
+    ui->sunrise->setTime(m_sunrise.time());
+    ui->sunset->setTime(m_sunset.time());
   } else {
-    settings.setValue("automaticTheme", false);
+    SettingsManager::instance().settings().setValue("automaticTheme", false);
     QMessageBox::critical(this, "Error",
                           "Invalid Geo-Coordinates.\n\nPlease try again.");
   }
 }
 
 void AutomaticTheme::on_save_clicked() {
-  if (sunrise.toSecsSinceEpoch() == sunset.toSecsSinceEpoch()) {
-    settings.setValue("automaticTheme", false);
-    QMessageBox::critical(this, "Error",
-                          "Invalid settings.\n\nSunrise and Sunset time cannot "
-                          "have similar values.\n\nPlease try again.");
+  if (m_sunrise.toSecsSinceEpoch() == m_sunset.toSecsSinceEpoch()) {
+    SettingsManager::instance().settings().setValue("automaticTheme", false);
+    QMessageBox::critical(
+        this, "Error",
+        "Invalid SettingsManager::instance().settings().\n\nSunrise and Sunset "
+        "time cannot "
+        "have similar values.\n\nPlease try again.");
   } else {
-    settings.setValue("sunrise", sunrise.toSecsSinceEpoch());
-    settings.setValue("sunset", sunset.toSecsSinceEpoch());
-    settings.setValue("automaticTheme", true);
+    SettingsManager::instance().settings().setValue(
+        "sunrise", m_sunrise.toSecsSinceEpoch());
+    SettingsManager::instance().settings().setValue(
+        "sunset", m_sunset.toSecsSinceEpoch());
+    SettingsManager::instance().settings().setValue("automaticTheme", true);
     this->close();
   }
 }
 
 void AutomaticTheme::on_cancel_clicked() {
-  settings.setValue("automaticTheme", false);
+  SettingsManager::instance().settings().setValue("automaticTheme", false);
   this->close();
 }
 
 void AutomaticTheme::on_sunrise_timeChanged(const QTime &time) {
-  sunrise.setTime(QTime(time.hour(), time.minute(), 0));
+  m_sunrise.setTime(QTime(time.hour(), time.minute(), 0));
 }
 
 void AutomaticTheme::on_sunset_timeChanged(const QTime &time) {
-  sunset.setTime(QTime(time.hour(), time.minute(), 0));
+  m_sunset.setTime(QTime(time.hour(), time.minute(), 0));
 }
diff --git a/src/automatictheme.h b/src/automatictheme.h
index 55904e5..f013713 100644
--- a/src/automatictheme.h
+++ b/src/automatictheme.h
@@ -1,47 +1,45 @@
 #ifndef AUTOMATICTHEME_H
 #define AUTOMATICTHEME_H
 
-#include <QWidget>
-#include <QGeoPositionInfoSource>
 #include <QDebug>
+#include <QGeoPositionInfoSource>
+#include <QMessageBox>
 #include <QTimeZone>
-#include <QSettings>
+#include <QWidget>
+
+#include "settingsmanager.h"
 
 namespace Ui {
 class AutomaticTheme;
 }
 
-class AutomaticTheme : public QWidget
-{
-    Q_OBJECT
+class AutomaticTheme : public QWidget {
+  Q_OBJECT
 
 public:
-    explicit AutomaticTheme(QWidget *parent = nullptr);
-    ~AutomaticTheme();
-
+  explicit AutomaticTheme(QWidget *parent = nullptr);
+  ~AutomaticTheme();
 
 private slots:
-    void on_refresh_clicked();
+  void on_refresh_clicked();
 
-    void on_save_clicked();
+  void on_save_clicked();
 
-    void on_cancel_clicked();
+  void on_cancel_clicked();
 
-    void on_sunrise_timeChanged(const QTime &time);
+  void on_sunrise_timeChanged(const QTime &time);
 
-    void on_sunset_timeChanged(const QTime &time);
+  void on_sunset_timeChanged(const QTime &time);
 
 private:
-    Ui::AutomaticTheme *ui;
-
-    QGeoPositionInfoSource *gPosInfoSrc;
-    QDateTime sunrise, sunset;
+  Ui::AutomaticTheme *ui;
 
-    double hour_offset = 0.0;
-    double lon = 0.0;
-    double lat = 0.0;
+  QGeoPositionInfoSource *m_gPosInfoSrc;
+  QDateTime m_sunrise, m_sunset;
 
-    QSettings settings;
+  double m_hourOffset = 0.0;
+  double m_longitude = 0.0;
+  double m_latitube = 0.0;
 };
 
 #endif // AUTOMATICTHEME_H
diff --git a/src/common.h b/src/common.h
index f7c32b9..295dd18 100644
--- a/src/common.h
+++ b/src/common.h
@@ -3,7 +3,8 @@
 #include <QString>
 
 // userAgent
-QString defaultUserAgentStr = "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/104.0.0.0 Safari/537.36";
+//QString defaultUserAgentStr = "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/104.0.0.0 Safari/537.36";
+QString defaultUserAgentStr = "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/113.0.0.0 Safari/537.36";
 
 //appAutoLock
 int defaultAppAutoLockDuration = 30;
diff --git a/src/dictionaries.cpp b/src/dictionaries.cpp
index fc8e7c0..5299806 100644
--- a/src/dictionaries.cpp
+++ b/src/dictionaries.cpp
@@ -19,7 +19,7 @@ QString Dictionaries::GetDictionaryPath() {
 
   // the environment variable takes precedence on all platforms
   if (qEnvironmentVariableIsSet("QTWEBENGINE_DICTIONARIES_PATH")) {
-    dict_path = utils::GetEnvironmentVar("QTWEBENGINE_DICTIONARIES_PATH");
+    dict_path = Utils::GetEnvironmentVar("QTWEBENGINE_DICTIONARIES_PATH");
     return dict_path;
   }
 
diff --git a/src/downloadmanagerwidget.cpp b/src/downloadmanagerwidget.cpp
index 812c471..13643e8 100644
--- a/src/downloadmanagerwidget.cpp
+++ b/src/downloadmanagerwidget.cpp
@@ -1,11 +1,6 @@
 #include "downloadmanagerwidget.h"

-

 #include "downloadwidget.h"

 

-#include <QFileDialog>

-#include <QStandardPaths>

-#include <QWebEngineDownloadItem>

-

 DownloadManagerWidget::DownloadManagerWidget(QWidget *parent)

     : QWidget(parent), m_numDownloads(0) {

   setupUi(this);

@@ -22,8 +17,7 @@ void DownloadManagerWidget::downloadRequested(
   Q_ASSERT(download &&

            download->state() == QWebEngineDownloadItem::DownloadRequested);

   QString path =

-      settings

-          .value("defaultDownloadLocation",

+      SettingsManager::instance().settings().value("defaultDownloadLocation",

                  QStandardPaths::writableLocation(

                      QStandardPaths::DownloadLocation) +

                      QDir::separator() + QApplication::applicationName())

@@ -46,7 +40,7 @@ void DownloadManagerWidget::downloadRequested(
     switch (msgBox.exec()) {

     case QMessageBox::Save: {

       QString n_proposed_file_name = path + QDir::separator() +

-                                     utils::generateRandomId(5) + "_" +

+                                     Utils::generateRandomId(5) + "_" +

                                      download->downloadFileName();

       download->setDownloadFileName(n_proposed_file_name);

       acceptDownload(download);

@@ -81,8 +75,7 @@ void DownloadManagerWidget::remove(DownloadWidget *downloadWidget) {
 }

 

 void DownloadManagerWidget::on_open_download_dir_clicked() {

-  utils::desktopOpenUrl(settings

-                            .value("defaultDownloadLocation",

+  Utils::desktopOpenUrl(SettingsManager::instance().settings().value("defaultDownloadLocation",

                                    QStandardPaths::writableLocation(

                                        QStandardPaths::DownloadLocation) +

                                        QDir::separator() +

diff --git a/src/downloadmanagerwidget.h b/src/downloadmanagerwidget.h
index 76464e8..8367041 100644
--- a/src/downloadmanagerwidget.h
+++ b/src/downloadmanagerwidget.h
@@ -51,10 +51,13 @@
 #ifndef DOWNLOADMANAGERWIDGET_H

 #define DOWNLOADMANAGERWIDGET_H

 

+#include "settingsmanager.h"

 #include "ui_downloadmanagerwidget.h"

-

 #include "utils.h"

-#include <QSettings>

+

+#include <QFileDialog>

+#include <QStandardPaths>

+#include <QWebEngineDownloadItem>

 #include <QWidget>

 

 QT_BEGIN_NAMESPACE

@@ -89,7 +92,6 @@ private:
   void remove(DownloadWidget *downloadWidget);

 

   int m_numDownloads;

-  QSettings settings;

 };

 

 #endif // DOWNLOADMANAGERWIDGET_H

diff --git a/src/lock.cpp b/src/lock.cpp
index ffbf144..3026573 100644
--- a/src/lock.cpp
+++ b/src/lock.cpp
@@ -1,10 +1,5 @@
 #include "lock.h"
-#include "moreapps.h"
 #include "ui_lock.h"
-#include <QDebug>
-#include <QGraphicsOpacityEffect>
-#include <QKeyEvent>
-#include <QPropertyAnimation>
 
 #include "X11/XKBlib.h" // keep this header at bottom
 
@@ -25,25 +20,28 @@ Lock::Lock(QWidget *parent) : QWidget(parent), ui(new Ui::Lock) {
   passcodeLoginAction = ui->passcodeLogin->addAction(
       QIcon(":/icons/green_arrow-right-line.png"), QLineEdit::TrailingPosition);
   passcodeLoginAction->setEnabled(false);
-  connect(passcodeLoginAction, &QAction::triggered, passcodeLoginAction,
-          [this]() {
-            QString password =
-                QByteArray::fromBase64(settings.value("asdfg").toByteArray());
-            if (ui->passcodeLogin->text() == password && check_password_set()) {
-              isLocked = false;
-              this->animateOut();
-              emit unLocked();
-            } else {
-              ui->wrong->show();
-            }
-          });
+  connect(
+      passcodeLoginAction, &QAction::triggered, passcodeLoginAction, [this]() {
+        QString password = QByteArray::fromBase64(SettingsManager::instance()
+                                                      .settings()
+                                                      .value("asdfg")
+                                                      .toByteArray());
+        if (ui->passcodeLogin->text() == password && check_password_set()) {
+          isLocked = false;
+          this->animateOut();
+          emit unLocked();
+        } else {
+          ui->wrong->show();
+        }
+      });
 
   QGraphicsOpacityEffect *eff = new QGraphicsOpacityEffect(this);
   ui->centerWidget->setGraphicsEffect(eff);
 
   animateIn();
 
-  if (settings.value("asdfg").isValid() == false) {
+  if (SettingsManager::instance().settings().value("asdfg").isValid() ==
+      false) {
     signUp();
   } else {
     lock_app();
@@ -143,7 +141,10 @@ void Lock::applyThemeQuirks() {
                    "border-bottom-left-radius: 4px;";
   QString lightBg = "background-color: rgb(37, 211, 102);";
   QString darkBg = "background-color: rgb(0, 117, 96);";
-  if (QString::compare(settings.value("windowTheme", "light").toString(),
+  if (QString::compare(SettingsManager::instance()
+                           .settings()
+                           .value("windowTheme", "light")
+                           .toString(),
                        "dark", Qt::CaseInsensitive) == 0) { // light
     ui->bottomLine->setStyleSheet(darkBg + border);
     ui->bottomLine_2->setStyleSheet(darkBg + border);
@@ -194,8 +195,9 @@ void Lock::on_setPass_clicked() {
   pass1 = ui->passcode1->text().trimmed();
   pass2 = ui->passcode2->text().trimmed();
   if (pass1 == pass2) {
-    settings.setValue("asdfg", QByteArray(pass1.toUtf8()).toBase64());
-    settings.setValue("lockscreen", true);
+    SettingsManager::instance().settings().setValue(
+        "asdfg", QByteArray(pass1.toUtf8()).toBase64());
+    SettingsManager::instance().settings().setValue("lockscreen", true);
     ui->passcode1->clear();
     ui->passcode2->clear();
     emit passwordSet();
@@ -207,7 +209,9 @@ void Lock::on_setPass_clicked() {
   }
 }
 
-bool Lock::check_password_set() { return settings.value("asdfg").isValid(); }
+bool Lock::check_password_set() {
+  return SettingsManager::instance().settings().value("asdfg").isValid();
+}
 
 void Lock::on_passcodeLogin_textChanged(const QString &arg1) {
   if (arg1.contains(" ")) {
@@ -231,12 +235,13 @@ void Lock::lock_app() {
 void Lock::on_passcodeLogin_returnPressed() { passcodeLoginAction->trigger(); }
 
 bool Lock::getCapsLockOn() {
-  Display *d = XOpenDisplay((char *)0);
+  Display *d = XOpenDisplay(nullptr);
   bool caps_state = false;
   if (d) {
     unsigned n;
     XkbGetIndicatorState(d, XkbUseCoreKbd, &n);
     caps_state = (n & 0x01) == 1;
+    XCloseDisplay(d);
   }
   return caps_state;
 }
diff --git a/src/lock.h b/src/lock.h
index 23af8e0..809ca3c 100644
--- a/src/lock.h
+++ b/src/lock.h
@@ -2,9 +2,15 @@
 #define LOCK_H
 
 #include <QAction>
-#include <QSettings>
+#include <QDebug>
+#include <QGraphicsOpacityEffect>
+#include <QKeyEvent>
+#include <QPropertyAnimation>
 #include <QWidget>
 
+#include "moreapps.h"
+#include "settingsmanager.h"
+
 namespace Ui {
 class Lock;
 }
@@ -47,7 +53,6 @@ protected slots:
 private:
   Ui::Lock *ui;
   bool isLocked = false;
-  QSettings settings;
   QAction *passcodeLoginAction;
 };
 
diff --git a/src/main.cpp b/src/main.cpp
index 5a17d78..c771f71 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,6 +1,5 @@
 #include <QApplication>
 #include <QDebug>
-#include <QSettings>
 #include <QWebEngineProfile>
 #include <QWebEngineSettings>
 #include <QtWebEngine>
@@ -9,6 +8,7 @@
 #include "common.h"
 #include "def.h"
 #include "mainwindow.h"
+#include "settingsmanager.h"
 #include <singleapplication.h>
 
 int main(int argc, char *argv[]) {
@@ -16,14 +16,18 @@ int main(int argc, char *argv[]) {
   QApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
 
 #ifdef QT_DEBUG
-  qputenv("QTWEBENGINE_CHROMIUM_FLAGS", "--remote-debugging-port=9421 --ignore-gpu-blocklist --no-sandbox");
+  qputenv("QTWEBENGINE_CHROMIUM_FLAGS",
+          "--remote-debugging-port=9421 --ignore-gpu-blocklist --no-sandbox "
+          "--single-process --disable-extensions");
 #else
-  qputenv("QTWEBENGINE_CHROMIUM_FLAGS", "--disable-logging --ignore-gpu-blocklist --no-sandbox"); //--single-process
+  qputenv("QTWEBENGINE_CHROMIUM_FLAGS",
+          "--disable-logging --ignore-gpu-blocklist --no-sandbox "
+          "--single-process --disable-extensions");
 #endif
 
   SingleApplication instance(argc, argv, true);
   instance.setQuitOnLastWindowClosed(false);
-  instance.setWindowIcon(QIcon(":/icons/app/icon-128.png"));
+  instance.setWindowIcon(QIcon(":/icons/app/icon-64.png"));
   QApplication::setApplicationName("WhatSie");
   QApplication::setDesktopFileName("com.ktechpit.whatsie");
   QApplication::setOrganizationDomain("com.ktechpit");
@@ -87,16 +91,16 @@ int main(int argc, char *argv[]) {
       QObject::tr("Show main window of running instance of ") +
           QApplication::applicationName());
 
-  parser.addOption(showCLIHelpOption);   // [x]
-  parser.addVersionOption();             // [x]
-  parser.addOption(buildInfoOption);     // [x]
-  parser.addOption(showAppWindowOption); // [x]
-  parser.addOption(openSettingsOption);  // [x]
-  parser.addOption(lockAppOption);       // [x]
-  parser.addOption(openAboutOption);     // [x]
-  parser.addOption(toggleThemeOption);   // [x]
-  parser.addOption(reloadAppOption);     // [x]
-  parser.addOption(newChatOption);       // [-]
+  parser.addOption(showCLIHelpOption);
+  parser.addVersionOption();
+  parser.addOption(buildInfoOption);
+  parser.addOption(showAppWindowOption);
+  parser.addOption(openSettingsOption);
+  parser.addOption(lockAppOption);
+  parser.addOption(openAboutOption);
+  parser.addOption(toggleThemeOption);
+  parser.addOption(reloadAppOption);
+  parser.addOption(newChatOption);
 
   secondaryInstanceCLIOptions << showAppWindowOption << openSettingsOption
                               << lockAppOption << openAboutOption
@@ -165,7 +169,10 @@ int main(int argc, char *argv[]) {
                   << "LockApp";
           whatsie.alreadyRunning();
           QSettings settings;
-          if (!settings.value("asdfg").isValid()) {
+          if (!SettingsManager::instance()
+                   .settings()
+                   .value("asdfg")
+                   .isValid()) {
             whatsie.notify(
                 QApplication::applicationName(),
                 QObject::tr("App lock is not configured, \n"
@@ -205,7 +212,7 @@ int main(int argc, char *argv[]) {
           qInfo() << "cmd:"
                   << "OpenNewChatPrompt";
           whatsie.alreadyRunning();
-          whatsie.newChat(); //TODO: invetigate the crash
+          whatsie.newChat(); // TODO: invetigate the crash
           return;
         }
 
@@ -238,7 +245,10 @@ int main(int argc, char *argv[]) {
 
   QSettings settings;
   if (QSystemTrayIcon::isSystemTrayAvailable() &&
-      settings.value("startMinimized", false).toBool()) {
+      SettingsManager::instance()
+          .settings()
+          .value("startMinimized", false)
+          .toBool()) {
     whatsie.runMinimized();
   } else {
     whatsie.show();
diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
index 72b6d4e..1ba43f1 100644
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -14,9 +14,10 @@ extern int defaultAppAutoLockDuration;
 extern bool defaultAppAutoLock;
 
 MainWindow::MainWindow(QWidget *parent)
-    : QMainWindow(parent), notificationsTitleRegExp("^\\([1-9]\\d*\\).*"),
-      trayIconNormal(":/icons/app/notification/whatsie-notify.png"),
-      unreadMessageCountRegExp("\\([^\\d]*(\\d+)[^\\d]*\\)") {
+    : QMainWindow(parent),
+      m_trayIconNormal(":/icons/app/notification/whatsie-notify.png"),
+      m_notificationsTitleRegExp("^\\([1-9]\\d*\\).*"),
+      m_unreadMessageCountRegExp("\\([^\\d]*(\\d+)[^\\d]*\\)") {
 
   setObjectName("MainWindow");
   setWindowTitle(QApplication::applicationName());
@@ -24,7 +25,6 @@ MainWindow::MainWindow(QWidget *parent)
   setMinimumWidth(525);
   setMinimumHeight(448);
   restoreMainWindow();
-  initThemes();
   createActions();
   createTrayIcon();
   createWebEngine();
@@ -36,8 +36,9 @@ MainWindow::MainWindow(QWidget *parent)
 }
 
 void MainWindow::restoreMainWindow() {
-  if (settings.value("geometry").isValid()) {
-    restoreGeometry(settings.value("geometry").toByteArray());
+  if (SettingsManager::instance().settings().value("geometry").isValid()) {
+    restoreGeometry(
+        SettingsManager::instance().settings().value("geometry").toByteArray());
     QPoint pos = QCursor::pos();
     auto localScreens = QGuiApplication::screens();
     for (auto screen : qAsConst(localScreens)) {
@@ -52,80 +53,30 @@ void MainWindow::restoreMainWindow() {
 }
 
 void MainWindow::initAutoLock() {
-  autoLockEventFilter = new AutoLockEventFilter(
-      settings.value("autoLockDuration", defaultAppAutoLockDuration).toInt() *
+  m_autoLockEventFilter = new AutoLockEventFilter(
+      SettingsManager::instance()
+          .settings()
+          .value("autoLockDuration", defaultAppAutoLockDuration)
+          .toInt() *
       1000);
-  connect(autoLockEventFilter, &AutoLockEventFilter::autoLockTimerTimeout, this,
-          [=]() {
-            if ((settingsWidget && !settingsWidget->isVisible()) &&
-                settings.value("appAutoLocking", defaultAppAutoLock).toBool()) {
+  connect(m_autoLockEventFilter, &AutoLockEventFilter::autoLockTimerTimeout,
+          this, [=]() {
+            if ((m_settingsWidget && !m_settingsWidget->isVisible()) &&
+                SettingsManager::instance()
+                    .settings()
+                    .value("appAutoLocking", defaultAppAutoLock)
+                    .toBool()) {
               this->lockApp();
             }
           });
-  if (settings.value("appAutoLocking", defaultAppAutoLock).toBool()) {
-    qApp->installEventFilter(autoLockEventFilter);
+  if (SettingsManager::instance()
+          .settings()
+          .value("appAutoLocking", defaultAppAutoLock)
+          .toBool()) {
+    qApp->installEventFilter(m_autoLockEventFilter);
   }
 }
 
-void MainWindow::initThemes() {
-  // Light
-  lightPalette.setColor(QPalette::Window, QColor(240, 240, 240));
-  lightPalette.setColor(QPalette::WindowText, QColor(0, 0, 0));
-  lightPalette.setColor(QPalette::Button, QColor(240, 240, 240));
-  lightPalette.setColor(QPalette::Light, QColor(180, 180, 180));
-  lightPalette.setColor(QPalette::Midlight, QColor(200, 200, 200));
-  lightPalette.setColor(QPalette::Dark, QColor(225, 225, 225));
-  lightPalette.setColor(QPalette::Text, QColor(0, 0, 0));
-  lightPalette.setColor(QPalette::BrightText, QColor(0, 0, 0));
-  lightPalette.setColor(QPalette::ButtonText, QColor(0, 0, 0));
-  lightPalette.setColor(QPalette::Base, QColor(237, 237, 237));
-  lightPalette.setColor(QPalette::Shadow, QColor(20, 20, 20));
-  lightPalette.setColor(QPalette::Highlight, QColor(76, 163, 224));
-  lightPalette.setColor(QPalette::HighlightedText, QColor(0, 0, 0));
-  lightPalette.setColor(QPalette::Link, QColor(0, 162, 232));
-  lightPalette.setColor(QPalette::AlternateBase, QColor(225, 225, 225));
-  lightPalette.setColor(QPalette::ToolTipBase, QColor(240, 240, 240));
-  lightPalette.setColor(QPalette::ToolTipText, QColor(0, 0, 0));
-  lightPalette.setColor(QPalette::LinkVisited, QColor(222, 222, 222));
-  lightPalette.setColor(QPalette::Disabled, QPalette::WindowText,
-                        QColor(115, 115, 115));
-  lightPalette.setColor(QPalette::Disabled, QPalette::Text,
-                        QColor(115, 115, 115));
-  lightPalette.setColor(QPalette::Disabled, QPalette::ButtonText,
-                        QColor(115, 115, 115));
-  lightPalette.setColor(QPalette::Disabled, QPalette::Highlight,
-                        QColor(190, 190, 190));
-  lightPalette.setColor(QPalette::Disabled, QPalette::HighlightedText,
-                        QColor(115, 115, 115));
-
-  // Dark
-  darkPalette.setColor(QPalette::Window, QColor(17, 27, 33));
-  darkPalette.setColor(QPalette::Text, Qt::white);
-  darkPalette.setColor(QPalette::WindowText, Qt::white);
-  darkPalette.setColor(QPalette::Base, QColor(32, 44, 51));
-  darkPalette.setColor(QPalette::AlternateBase, QColor(95, 108, 115));
-  darkPalette.setColor(QPalette::ToolTipBase, QColor(66, 66, 66));
-  darkPalette.setColor(QPalette::ToolTipText, QColor(192, 192, 192));
-  darkPalette.setColor(QPalette::Dark, QColor(35, 35, 35));
-  darkPalette.setColor(QPalette::Shadow, QColor(20, 20, 20));
-  darkPalette.setColor(QPalette::Button, QColor(17, 27, 33));
-  darkPalette.setColor(QPalette::ButtonText, Qt::white);
-  darkPalette.setColor(QPalette::BrightText, Qt::red);
-  darkPalette.setColor(QPalette::Link, QColor(42, 130, 218));
-  darkPalette.setColor(QPalette::Highlight, QColor(38, 140, 196));
-  darkPalette.setColor(QPalette::HighlightedText, Qt::white);
-  darkPalette.setColor(QPalette::Disabled, QPalette::HighlightedText,
-                       QColor(127, 127, 127));
-  darkPalette.setColor(QPalette::Disabled, QPalette::Window,
-                       QColor(65, 65, 67));
-  darkPalette.setColor(QPalette::Disabled, QPalette::Highlight,
-                       QColor(80, 80, 80));
-  darkPalette.setColor(QPalette::Disabled, QPalette::ButtonText,
-                       QColor(127, 127, 127));
-  darkPalette.setColor(QPalette::Disabled, QPalette::Text,
-                       QColor(127, 127, 127));
-}
-
 void MainWindow::initRateWidget() {
   RateApp *rateApp = new RateApp(this, "snap://whatsie", 5, 5, 1000 * 30);
   rateApp->setWindowTitle(QApplication::applicationName() + " | " +
@@ -146,11 +97,11 @@ void MainWindow::initRateWidget() {
 }
 
 void MainWindow::runMinimized() {
-  this->minimizeAction->trigger();
+  this->m_minimizeAction->trigger();
   notify("Whatsie", "Whatsie started minimized in tray. Click to Open.");
 }
 
-MainWindow::~MainWindow() { webEngine->deleteLater(); }
+MainWindow::~MainWindow() { m_webEngine->deleteLater(); }
 
 void MainWindow::loadSchemaUrl(const QString &arg) {
   // https://faq.whatsapp.com/iphone/how-to-link-to-whatsapp-from-a-different-app/?lang=en
@@ -172,45 +123,53 @@ void MainWindow::loadSchemaUrl(const QString &arg) {
 }
 
 void MainWindow::updatePageTheme() {
-  if (webEngine && webEngine->page()) {
+  if (m_webEngine && m_webEngine->page()) {
 
-    QString windowTheme = settings.value("windowTheme", "light").toString();
+    QString windowTheme = SettingsManager::instance()
+                              .settings()
+                              .value("windowTheme", "light")
+                              .toString();
 
     if (windowTheme == "dark") {
-      webEngine->page()->runJavaScript(
+      m_webEngine->page()->runJavaScript(
           "localStorage['system-theme-mode']='false'; "
           "localStorage.theme='\"dark\"'; ");
 
-      webEngine->page()->runJavaScript(
+      m_webEngine->page()->runJavaScript(
           "document.querySelector('body').classList.add('" + windowTheme +
           "');");
     } else {
-      webEngine->page()->runJavaScript(
+      m_webEngine->page()->runJavaScript(
           "localStorage['system-theme-mode']='false'; "
           "localStorage.theme='\"light\"'; ");
 
-      webEngine->page()->runJavaScript(
+      m_webEngine->page()->runJavaScript(
           "document.querySelector('body').classList.remove('dark');");
     }
   }
 }
 
 void MainWindow::resizeEvent(QResizeEvent *event) {
-  if (lockWidget != nullptr) {
-    lockWidget->resize(event->size());
+  if (m_lockWidget != nullptr) {
+    m_lockWidget->resize(event->size());
   }
 }
 
 void MainWindow::updateWindowTheme() {
-  qApp->setStyle(QStyleFactory::create(
-      settings.value("widgetStyle", "Fusion").toString()));
-  if (settings.value("windowTheme", "light").toString() == "dark") {
-    qApp->setPalette(darkPalette);
-    webEngine->setStyleSheet(
+  qApp->setStyle(QStyleFactory::create(SettingsManager::instance()
+                                           .settings()
+                                           .value("widgetStyle", "Fusion")
+                                           .toString()));
+  if (SettingsManager::instance()
+          .settings()
+          .value("windowTheme", "light")
+          .toString() == "dark") {
+    qApp->setPalette(Theme::getDarkPalette());
+    m_webEngine->setStyleSheet(
         "QWebEngineView{background:rgb(17, 27, 33);}"); // whatsapp dark color
   } else {
-    qApp->setPalette(lightPalette);
-    webEngine->setStyleSheet(
+    qApp->setPalette(Theme::getLightPalette());
+    m_webEngine->setStyleSheet(
         "QWebEngineView{background:#F0F0F0;}"); // whatsapp light color
   }
 
@@ -218,13 +177,13 @@ void MainWindow::updateWindowTheme() {
   foreach (QWidget *w, widgets) {
     w->setPalette(qApp->palette());
   }
-  setNotificationPresenter(webEngine->page()->profile());
+  setNotificationPresenter(m_webEngine->page()->profile());
 
-  if (lockWidget != nullptr) {
-    lockWidget->setStyleSheet(
+  if (m_lockWidget != nullptr) {
+    m_lockWidget->setStyleSheet(
         "QWidget#login{background-color:palette(window)};"
         "QWidget#signup{background-color:palette(window)};");
-    lockWidget->applyThemeQuirks();
+    m_lockWidget->applyThemeQuirks();
   }
   this->update();
 }
@@ -234,8 +193,8 @@ void MainWindow::handleCookieAdded(const QNetworkCookie &cookie) {
 }
 
 void MainWindow::forceLogOut() {
-  if (webEngine && webEngine->page()) {
-    webEngine->page()->runJavaScript(
+  if (m_webEngine && m_webEngine->page()) {
+    m_webEngine->page()->runJavaScript(
         "window.localStorage.clear();",
         [=](const QVariant &result) { qDebug() << result; });
   }
@@ -243,8 +202,8 @@ void MainWindow::forceLogOut() {
 
 bool MainWindow::isLoggedIn() {
   static bool loggedIn = false;
-  if (webEngine && webEngine->page()) {
-    webEngine->page()->runJavaScript(
+  if (m_webEngine && m_webEngine->page()) {
+    m_webEngine->page()->runJavaScript(
         "window.localStorage.getItem('last-wid-md')",
         [=](const QVariant &result) {
           qDebug() << Q_FUNC_INFO << result;
@@ -261,8 +220,8 @@ bool MainWindow::isLoggedIn() {
 }
 
 void MainWindow::tryLogOut() {
-  if (webEngine && webEngine->page()) {
-    webEngine->page()->runJavaScript(
+  if (m_webEngine && m_webEngine->page()) {
+    m_webEngine->page()->runJavaScript(
         "document.querySelector(\"span[data-testid|='menu']\").click();"
         "document.querySelector(\"#side > header > div > div > span > div > "
         "span > div > ul > li:nth-child(4) > div\").click();"
@@ -280,108 +239,116 @@ void MainWindow::tryLogOut() {
 
 void MainWindow::initSettingWidget() {
   int screenNumber = qApp->desktop()->screenNumber(this);
-  if (settingsWidget == nullptr) {
-    settingsWidget = new SettingsWidget(
-        this, screenNumber, webEngine->page()->profile()->cachePath(),
-        webEngine->page()->profile()->persistentStoragePath());
-    settingsWidget->setWindowTitle(QApplication::applicationName() +
-                                   " | Settings");
-    settingsWidget->setWindowFlags(Qt::Dialog);
-
-    connect(settingsWidget, SIGNAL(initLock()), this, SLOT(initLock()));
-    connect(settingsWidget, SIGNAL(changeLockPassword()), this,
-            SLOT(changeLockPassword()));
-    connect(settingsWidget, SIGNAL(appAutoLockChanged()), this,
-            SLOT(appAutoLockChanged()));
-
-    connect(settingsWidget, SIGNAL(updateWindowTheme()), this,
-            SLOT(updateWindowTheme()));
-    connect(settingsWidget, SIGNAL(updatePageTheme()), this,
-            SLOT(updatePageTheme()));
-
-    connect(settingsWidget, &SettingsWidget::muteToggled, settingsWidget,
-            [=](const bool checked) { this->toggleMute(checked); });
-    connect(settingsWidget, &SettingsWidget::userAgentChanged, settingsWidget,
-            [=](QString userAgentStr) {
-              if (webEngine->page()->profile()->httpUserAgent() !=
+  if (m_settingsWidget == nullptr) {
+    m_settingsWidget = new SettingsWidget(
+        this, screenNumber, m_webEngine->page()->profile()->cachePath(),
+        m_webEngine->page()->profile()->persistentStoragePath());
+    m_settingsWidget->setWindowTitle(QApplication::applicationName() +
+                                     " | Settings");
+    m_settingsWidget->setWindowFlags(Qt::Dialog);
+
+    connect(m_settingsWidget, &SettingsWidget::initLock, this,
+            &MainWindow::initLock);
+    connect(m_settingsWidget, &SettingsWidget::changeLockPassword, this,
+            &MainWindow::changeLockPassword);
+    connect(m_settingsWidget, &SettingsWidget::appAutoLockChanged, this,
+            &MainWindow::appAutoLockChanged);
+
+    connect(m_settingsWidget, &SettingsWidget::updateWindowTheme, this,
+            &MainWindow::updateWindowTheme);
+    connect(m_settingsWidget, &SettingsWidget::updatePageTheme, this,
+            &MainWindow::updatePageTheme);
+
+    connect(m_settingsWidget, &SettingsWidget::muteToggled, this,
+            &MainWindow::toggleMute);
+    connect(m_settingsWidget, &SettingsWidget::userAgentChanged,
+            m_settingsWidget, [=](QString userAgentStr) {
+              if (m_webEngine->page()->profile()->httpUserAgent() !=
                   userAgentStr) {
-                settings.setValue("useragent", userAgentStr);
+                SettingsManager::instance().settings().setValue("useragent",
+                                                                userAgentStr);
                 this->updateSettingsUserAgentWidget();
                 this->askToReloadPage();
               }
             });
-    connect(settingsWidget, &SettingsWidget::autoPlayMediaToggled,
-            settingsWidget, [=](bool checked) {
+    connect(m_settingsWidget, &SettingsWidget::autoPlayMediaToggled,
+            m_settingsWidget, [=](bool checked) {
               QWebEngineProfile *profile = QWebEngineProfile::defaultProfile();
               auto *webSettings = profile->settings();
               webSettings->setAttribute(
                   QWebEngineSettings::PlaybackRequiresUserGesture, checked);
 
-              webEngine->page()->profile()->settings()->setAttribute(
+              m_webEngine->page()->profile()->settings()->setAttribute(
                   QWebEngineSettings::PlaybackRequiresUserGesture, checked);
             });
 
-    connect(settingsWidget, &SettingsWidget::dictChanged, settingsWidget,
+    connect(m_settingsWidget, &SettingsWidget::dictChanged, m_settingsWidget,
             [=](QString dictName) {
-              if (webEngine && webEngine->page()) {
-                webEngine->page()->profile()->setSpellCheckLanguages(
+              if (m_webEngine && m_webEngine->page()) {
+                m_webEngine->page()->profile()->setSpellCheckLanguages(
                     QStringList() << dictName);
               }
             });
 
-    connect(settingsWidget, &SettingsWidget::spellCheckChanged, settingsWidget,
-            [=](bool checked) {
-              if (webEngine && webEngine->page()) {
-                webEngine->page()->profile()->setSpellCheckEnabled(checked);
+    connect(m_settingsWidget, &SettingsWidget::spellCheckChanged,
+            m_settingsWidget, [=](bool checked) {
+              if (m_webEngine && m_webEngine->page()) {
+                m_webEngine->page()->profile()->setSpellCheckEnabled(checked);
               }
             });
 
-    connect(
-        settingsWidget, &SettingsWidget::zoomChanged, settingsWidget, [=]() {
-          if (windowState() == Qt::WindowNoState) {
-            double currentFactor = settings.value("zoomFactor", 1.0).toDouble();
-            webEngine->page()->setZoomFactor(currentFactor);
-          }
-        });
+    connect(m_settingsWidget, &SettingsWidget::zoomChanged, m_settingsWidget,
+            [=]() {
+              if (windowState() == Qt::WindowNoState) {
+                double currentFactor = SettingsManager::instance()
+                                           .settings()
+                                           .value("zoomFactor", 1.0)
+                                           .toDouble();
+                m_webEngine->page()->setZoomFactor(currentFactor);
+              }
+            });
 
-    connect(settingsWidget, &SettingsWidget::zoomMaximizedChanged,
-            settingsWidget, [=]() {
+    connect(m_settingsWidget, &SettingsWidget::zoomMaximizedChanged,
+            m_settingsWidget, [=]() {
               if (windowState() == Qt::WindowMaximized ||
                   windowState() == Qt::WindowFullScreen) {
-                double currentFactor = settings
+                double currentFactor = SettingsManager::instance()
+                                           .settings()
                                            .value("zoomFactorMaximized",
                                                   defaultZoomFactorMaximized)
                                            .toDouble();
-                webEngine->page()->setZoomFactor(currentFactor);
+                m_webEngine->page()->setZoomFactor(currentFactor);
               }
             });
 
-    connect(settingsWidget, &SettingsWidget::notificationPopupTimeOutChanged,
-            settingsWidget,
-            [=]() { setNotificationPresenter(webEngine->page()->profile()); });
+    connect(m_settingsWidget, &SettingsWidget::notificationPopupTimeOutChanged,
+            m_settingsWidget, [=]() {
+              setNotificationPresenter(m_webEngine->page()->profile());
+            });
 
-    connect(settingsWidget, &SettingsWidget::notify, settingsWidget,
+    connect(m_settingsWidget, &SettingsWidget::notify, m_settingsWidget,
             [=](QString message) { notify("", message); });
 
-    connect(settingsWidget, &SettingsWidget::updateFullWidthView,
-            settingsWidget, [=](bool checked) {
-              if (webEngine && webEngine->page()) {
+    connect(m_settingsWidget, &SettingsWidget::updateFullWidthView,
+            m_settingsWidget, [=](bool checked) {
+              if (m_webEngine && m_webEngine->page()) {
                 if (checked)
-                  webEngine->page()->runJavaScript(
+                  m_webEngine->page()->runJavaScript(
                       "document.querySelector('body').classList.add('whatsie-"
                       "full-view');");
                 else
-                  webEngine->page()->runJavaScript(
+                  m_webEngine->page()->runJavaScript(
                       "document.querySelector('body').classList.remove('"
                       "whatsie-full-view');");
               }
             });
 
-    settingsWidget->appLockSetChecked(
-        settings.value("lockscreen", false).toBool());
+    m_settingsWidget->appLockSetChecked(SettingsManager::instance()
+                                            .settings()
+                                            .value("lockscreen", false)
+                                            .toBool());
 
-    // spell checker
-    settingsWidget->loadDictionaries(dictionaries);
+    m_settingsWidget->loadDictionaries(m_dictionaries);
   }
 }
 
@@ -394,15 +361,15 @@ void MainWindow::changeEvent(QEvent *e) {
 
 void MainWindow::handleZoomOnWindowStateChange(
     const QWindowStateChangeEvent *ev) {
-  if (settingsWidget != nullptr) {
+  if (m_settingsWidget != nullptr) {
     if (ev->oldState().testFlag(Qt::WindowMaximized) &&
         windowState().testFlag(Qt::WindowNoState)) {
-      emit settingsWidget->zoomChanged();
+      emit m_settingsWidget->zoomChanged();
     } else if ((!ev->oldState().testFlag(Qt::WindowMaximized) &&
                 windowState().testFlag(Qt::WindowMaximized)) ||
                (!ev->oldState().testFlag(Qt::WindowMaximized) &&
                 windowState().testFlag(Qt::WindowFullScreen))) {
-      emit settingsWidget->zoomMaximizedChanged();
+      emit m_settingsWidget->zoomMaximizedChanged();
     }
   }
 }
@@ -411,22 +378,27 @@ void MainWindow::handleZoom() {
   if (windowState().testFlag(Qt::WindowMaximized) ||
       windowState().testFlag(Qt::WindowFullScreen)) {
     double currentFactor =
-        settings.value("zoomFactorMaximized", defaultZoomFactorMaximized)
+        SettingsManager::instance()
+            .settings()
+            .value("zoomFactorMaximized", defaultZoomFactorMaximized)
             .toDouble();
-    webEngine->page()->setZoomFactor(currentFactor);
+    m_webEngine->page()->setZoomFactor(currentFactor);
   } else if (windowState().testFlag(Qt::WindowNoState)) {
-    double currentFactor = settings.value("zoomFactor", 1.0).toDouble();
-    webEngine->page()->setZoomFactor(currentFactor);
+    double currentFactor = SettingsManager::instance()
+                               .settings()
+                               .value("zoomFactor", 1.0)
+                               .toDouble();
+    m_webEngine->page()->setZoomFactor(currentFactor);
   }
 }
 
 void MainWindow::lockApp() {
-  if (lockWidget != nullptr && lockWidget->getIsLocked())
+  if (m_lockWidget != nullptr && m_lockWidget->getIsLocked())
     return;
 
-  if (settings.value("asdfg").isValid()) {
+  if (SettingsManager::instance().settings().value("asdfg").isValid()) {
     initLock();
-    lockWidget->lock_app();
+    m_lockWidget->lock_app();
   } else {
     int ret = QMessageBox::information(
         this, tr(QApplication::applicationName().toUtf8()),
@@ -441,13 +413,13 @@ void MainWindow::lockApp() {
 }
 
 void MainWindow::toggleTheme() {
-  if (settingsWidget != nullptr) {
-    settingsWidget->toggleTheme();
+  if (m_settingsWidget != nullptr) {
+    m_settingsWidget->toggleTheme();
   }
 }
 
 void MainWindow::showSettings(bool isAskedByCLI) {
-  if (lockWidget && lockWidget->getIsLocked()) {
+  if (m_lockWidget && m_lockWidget->getIsLocked()) {
     QString error = tr("Unlock to access Settings.");
     if (isAskedByCLI) {
       this->notify(QApplication::applicationName() + "| Error", error);
@@ -459,28 +431,28 @@ void MainWindow::showSettings(bool isAskedByCLI) {
     return;
   }
 
-  if (webEngine == nullptr) {
+  if (m_webEngine == nullptr) {
     QMessageBox::critical(
         this, QApplication::applicationName() + "| Error",
         "Unable to initialize settings module.\nWebengine is not initialized.");
     return;
   }
-  if (!settingsWidget->isVisible()) {
+  if (!m_settingsWidget->isVisible()) {
     this->updateSettingsUserAgentWidget();
-    settingsWidget->refresh();
+    m_settingsWidget->refresh();
     int screenNumber = qApp->desktop()->screenNumber(this);
     QRect screenRect = QGuiApplication::screens().at(screenNumber)->geometry();
-    if (!screenRect.contains(settingsWidget->pos())) {
-      settingsWidget->move(screenRect.center() -
-                           settingsWidget->rect().center());
+    if (!screenRect.contains(m_settingsWidget->pos())) {
+      m_settingsWidget->move(screenRect.center() -
+                             m_settingsWidget->rect().center());
     }
-    settingsWidget->show();
+    m_settingsWidget->show();
   }
 }
 
 void MainWindow::updateSettingsUserAgentWidget() {
-  settingsWidget->updateDefaultUAButton(
-      webEngine->page()->profile()->httpUserAgent());
+  m_settingsWidget->updateDefaultUAButton(
+      m_webEngine->page()->profile()->httpUserAgent());
 }
 
 void MainWindow::askToReloadPage() {
@@ -497,22 +469,29 @@ void MainWindow::showAbout() {
   about->setWindowFlag(Qt::Dialog);
   about->setMinimumSize(about->sizeHint());
   about->adjustSize();
-  about->setAttribute(Qt::WA_DeleteOnClose);
+  about->setAttribute(Qt::WA_DeleteOnClose, true);
   about->show();
 }
 
 void MainWindow::closeEvent(QCloseEvent *event) {
-  settings.setValue("geometry", saveGeometry());
+  SettingsManager::instance().settings().setValue("geometry", saveGeometry());
   getPageTheme();
-  QTimer::singleShot(500, settingsWidget, [=]() { settingsWidget->refresh(); });
+  QTimer::singleShot(500, m_settingsWidget,
+                     [=]() { m_settingsWidget->refresh(); });
 
   if (QSystemTrayIcon::isSystemTrayAvailable() &&
-      settings.value("closeButtonActionCombo", 0).toInt() == 0) {
+      SettingsManager::instance()
+              .settings()
+              .value("closeButtonActionCombo", 0)
+              .toInt() == 0) {
     this->hide();
     event->ignore();
-    if (settings.value("firstrun_tray", true).toBool()) {
+    if (SettingsManager::instance()
+            .settings()
+            .value("firstrun_tray", true)
+            .toBool()) {
       notify(QApplication::applicationName(), "Minimized to system tray.");
-      settings.setValue("firstrun_tray", false);
+      SettingsManager::instance().settings().setValue("firstrun_tray", false);
     }
     return;
   }
@@ -523,28 +502,38 @@ void MainWindow::closeEvent(QCloseEvent *event) {
 
 void MainWindow::notify(QString title, QString message) {
 
-  if (settings.value("disableNotificationPopups", false).toBool() == true) {
+  if (SettingsManager::instance()
+          .settings()
+          .value("disableNotificationPopups", false)
+          .toBool() == true) {
     return;
   }
 
   if (title.isEmpty())
     title = QApplication::applicationName();
 
-  if (settings.value("notificationCombo", 1).toInt() == 0 &&
-      trayIcon != nullptr) {
-    trayIcon->showMessage(title, message,
-                          QIcon(":/icons/app/notification/whatsie-notify.png"),
-                          settings.value("notificationTimeOut", 9000).toInt());
-    trayIcon->disconnect(trayIcon, SIGNAL(messageClicked()));
-    connect(trayIcon, &QSystemTrayIcon::messageClicked, trayIcon, [=]() {
-      if (windowState().testFlag(Qt::WindowMinimized) ||
-          !windowState().testFlag(Qt::WindowActive)) {
-        activateWindow();
-        this->show();
-      }
-    });
+  if (SettingsManager::instance()
+              .settings()
+              .value("notificationCombo", 1)
+              .toInt() == 0 &&
+      m_systemTrayIcon != nullptr) {
+    m_systemTrayIcon->showMessage(
+        title, message, QIcon(":/icons/app/notification/whatsie-notify.png"),
+        SettingsManager::instance()
+            .settings()
+            .value("notificationTimeOut", 9000)
+            .toInt());
+    m_systemTrayIcon->disconnect(m_systemTrayIcon, SIGNAL(messageClicked()));
+    connect(m_systemTrayIcon, &QSystemTrayIcon::messageClicked,
+            m_systemTrayIcon, [=]() {
+              if (windowState().testFlag(Qt::WindowMinimized) ||
+                  !windowState().testFlag(Qt::WindowActive)) {
+                activateWindow();
+                this->show();
+              }
+            });
   } else {
-    auto popup = new NotificationPopup(webEngine);
+    auto popup = new NotificationPopup(m_webEngine);
     connect(popup, &NotificationPopup::notification_clicked, popup, [=]() {
       if (windowState().testFlag(Qt::WindowMinimized) ||
           !windowState().testFlag(Qt::WindowActive) || this->isHidden()) {
@@ -564,98 +553,102 @@ void MainWindow::notify(QString title, QString message) {
 
 void MainWindow::createActions() {
 
-  openUrlAction = new QAction("New Chat", this);
-  openUrlAction->setShortcut(QKeySequence(Qt::Modifier::CTRL + Qt::Key_N));
-  connect(openUrlAction, &QAction::triggered, this, &MainWindow::newChat);
-  addAction(openUrlAction);
+  m_openUrlAction = new QAction("New Chat", this);
+  m_openUrlAction->setShortcut(QKeySequence(Qt::Modifier::CTRL + Qt::Key_N));
+  connect(m_openUrlAction, &QAction::triggered, this, &MainWindow::newChat);
+  addAction(m_openUrlAction);
 
-  fullscreenAction = new QAction(tr("Fullscreen"), this);
-  fullscreenAction->setShortcut(Qt::Key_F11);
-  connect(fullscreenAction, &QAction::triggered, fullscreenAction,
+  m_fullscreenAction = new QAction(tr("Fullscreen"), this);
+  m_fullscreenAction->setShortcut(Qt::Key_F11);
+  connect(m_fullscreenAction, &QAction::triggered, m_fullscreenAction,
           [=]() { setWindowState(windowState() ^ Qt::WindowFullScreen); });
-  addAction(fullscreenAction);
+  addAction(m_fullscreenAction);
 
-  minimizeAction = new QAction(tr("Mi&nimize to tray"), this);
-  connect(minimizeAction, &QAction::triggered, this, &QMainWindow::hide);
-  addAction(minimizeAction);
+  m_minimizeAction = new QAction(tr("Mi&nimize to tray"), this);
+  connect(m_minimizeAction, &QAction::triggered, this, &QMainWindow::hide);
+  addAction(m_minimizeAction);
 
   QShortcut *minimizeShortcut = new QShortcut(
       QKeySequence(Qt::Modifier::CTRL + Qt::Key_W), this, SLOT(hide()));
   minimizeShortcut->setAutoRepeat(false);
 
-  restoreAction = new QAction(tr("&Restore"), this);
-  connect(restoreAction, &QAction::triggered, this, &QMainWindow::show);
-  addAction(restoreAction);
-
-  reloadAction = new QAction(tr("Re&load"), this);
-  reloadAction->setShortcut(Qt::Key_F5);
-  connect(reloadAction, &QAction::triggered, this, [=] { this->doReload(); });
-  addAction(reloadAction);
-
-  lockAction = new QAction(tr("Loc&k"), this);
-  lockAction->setShortcut(QKeySequence(Qt::Modifier::CTRL + Qt::Key_L));
-  connect(lockAction, &QAction::triggered, this, &MainWindow::lockApp);
-  addAction(lockAction);
-
-  settingsAction = new QAction(tr("&Settings"), this);
-  settingsAction->setShortcut(QKeySequence(Qt::Modifier::CTRL + Qt::Key_P));
-  connect(settingsAction, &QAction::triggered, this, &MainWindow::showSettings);
-  addAction(settingsAction);
-
-  toggleThemeAction = new QAction(tr("&Toggle theme"), this);
-  toggleThemeAction->setShortcut(QKeySequence(Qt::Modifier::CTRL + Qt::Key_T));
-  connect(toggleThemeAction, &QAction::triggered, this,
+  m_restoreAction = new QAction(tr("&Restore"), this);
+  connect(m_restoreAction, &QAction::triggered, this, &QMainWindow::show);
+  addAction(m_restoreAction);
+
+  m_reloadAction = new QAction(tr("Re&load"), this);
+  m_reloadAction->setShortcut(Qt::Key_F5);
+  connect(m_reloadAction, &QAction::triggered, this,
+          [=]() { this->doReload(); });
+  addAction(m_reloadAction);
+
+  m_lockAction = new QAction(tr("Loc&k"), this);
+  m_lockAction->setShortcut(QKeySequence(Qt::Modifier::CTRL + Qt::Key_L));
+  connect(m_lockAction, &QAction::triggered, this, &MainWindow::lockApp);
+  addAction(m_lockAction);
+
+  m_settingsAction = new QAction(tr("&Settings"), this);
+  m_settingsAction->setShortcut(QKeySequence(Qt::Modifier::CTRL + Qt::Key_P));
+  connect(m_settingsAction, &QAction::triggered, this,
+          &MainWindow::showSettings);
+  addAction(m_settingsAction);
+
+  m_toggleThemeAction = new QAction(tr("&Toggle theme"), this);
+  m_toggleThemeAction->setShortcut(
+      QKeySequence(Qt::Modifier::CTRL + Qt::Key_T));
+  connect(m_toggleThemeAction, &QAction::triggered, this,
           &MainWindow::toggleTheme);
-  addAction(toggleThemeAction);
+  addAction(m_toggleThemeAction);
 
-  aboutAction = new QAction(tr("&About"), this);
-  connect(aboutAction, &QAction::triggered, this, &MainWindow::showAbout);
+  m_aboutAction = new QAction(tr("&About"), this);
+  connect(m_aboutAction, &QAction::triggered, this, &MainWindow::showAbout);
 
-  quitAction = new QAction(tr("&Quit"), this);
-  quitAction->setShortcut(QKeySequence(Qt::Modifier::CTRL + Qt::Key_Q));
-  connect(quitAction, &QAction::triggered, this, &MainWindow::quitApp);
-  addAction(quitAction);
+  m_quitAction = new QAction(tr("&Quit"), this);
+  m_quitAction->setShortcut(QKeySequence(Qt::Modifier::CTRL + Qt::Key_Q));
+  connect(m_quitAction, &QAction::triggered, this, &MainWindow::quitApp);
+  addAction(m_quitAction);
 }
 
 void MainWindow::quitApp() {
-  settings.setValue("geometry", saveGeometry());
+  SettingsManager::instance().settings().setValue("geometry", saveGeometry());
   getPageTheme();
-  QTimer::singleShot(500, &settings, [=]() {
-    settings.setValue("firstrun_tray", true);
+  QTimer::singleShot(500, this, [=]() {
+    SettingsManager::instance().settings().setValue("firstrun_tray", true);
     qApp->quit();
   });
 }
 
 void MainWindow::createTrayIcon() {
-  trayIconMenu = new QMenu(this);
-  trayIconMenu->setObjectName("trayIconMenu");
-  trayIconMenu->addAction(minimizeAction);
-  trayIconMenu->addAction(restoreAction);
-  trayIconMenu->addSeparator();
-  trayIconMenu->addAction(reloadAction);
-  trayIconMenu->addAction(lockAction);
-  trayIconMenu->addSeparator();
-  trayIconMenu->addAction(openUrlAction);
-  trayIconMenu->addAction(toggleThemeAction);
-  trayIconMenu->addAction(settingsAction);
-  trayIconMenu->addAction(aboutAction);
-  trayIconMenu->addSeparator();
-  trayIconMenu->addAction(quitAction);
-
-  trayIcon = new QSystemTrayIcon(trayIconNormal, this);
-  trayIcon->setContextMenu(trayIconMenu);
-  connect(trayIconMenu, SIGNAL(aboutToShow()), this, SLOT(checkWindowState()));
-
-  trayIcon->show();
-
-  connect(trayIcon, &QSystemTrayIcon::messageClicked, this,
+  m_trayIconMenu = new QMenu(this);
+  m_trayIconMenu->setObjectName("trayIconMenu");
+  m_trayIconMenu->addAction(m_minimizeAction);
+  m_trayIconMenu->addAction(m_restoreAction);
+  m_trayIconMenu->addSeparator();
+  m_trayIconMenu->addAction(m_reloadAction);
+  m_trayIconMenu->addAction(m_lockAction);
+  m_trayIconMenu->addSeparator();
+  m_trayIconMenu->addAction(m_openUrlAction);
+  m_trayIconMenu->addAction(m_toggleThemeAction);
+  m_trayIconMenu->addAction(m_settingsAction);
+  m_trayIconMenu->addAction(m_aboutAction);
+  m_trayIconMenu->addSeparator();
+  m_trayIconMenu->addAction(m_quitAction);
+
+  m_systemTrayIcon = new QSystemTrayIcon(m_trayIconNormal, this);
+  m_systemTrayIcon->setContextMenu(m_trayIconMenu);
+  connect(m_trayIconMenu, &QMenu::aboutToShow, this,
+          &MainWindow::checkWindowState);
+
+  m_systemTrayIcon->show();
+
+  connect(m_systemTrayIcon, &QSystemTrayIcon::messageClicked, this,
           &MainWindow::messageClicked);
-  connect(trayIcon, &QSystemTrayIcon::activated, this,
+  connect(m_systemTrayIcon, &QSystemTrayIcon::activated, this,
           &MainWindow::iconActivated);
 
   // enable show shortcuts in menu
   if (qApp->styleHints()->showShortcutsInContextMenus()) {
-    foreach (QAction *action, trayIconMenu->actions()) {
+    foreach (QAction *action, m_trayIconMenu->actions()) {
       action->setShortcutVisibleInContextMenu(true);
     }
   }
@@ -663,58 +656,64 @@ void MainWindow::createTrayIcon() {
 
 void MainWindow::initLock() {
 
-  if (lockWidget == nullptr) {
-    lockWidget = new Lock(this);
-    lockWidget->setObjectName("lockWidget");
+  if (m_lockWidget == nullptr) {
+    m_lockWidget = new Lock(this);
+    m_lockWidget->setObjectName("lockWidget");
 
-    lockWidget->setWindowFlags(Qt::Widget);
-    lockWidget->setStyleSheet(
+    m_lockWidget->setWindowFlags(Qt::Widget);
+    m_lockWidget->setStyleSheet(
         "QWidget#login{background-color:palette(window)};"
         "QWidget#signup{background-color:palette(window)}");
-    lockWidget->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
+    m_lockWidget->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
 
-    connect(lockWidget, &Lock::passwordNotSet, settingsWidget, [=]() {
-      settings.setValue("lockscreen", false);
-      settingsWidget->appLockSetChecked(false);
+    connect(m_lockWidget, &Lock::passwordNotSet, m_settingsWidget, [=]() {
+      SettingsManager::instance().settings().setValue("lockscreen", false);
+      m_settingsWidget->appLockSetChecked(false);
     });
 
-    connect(lockWidget, &Lock::unLocked, [=]() {
+    connect(m_lockWidget, &Lock::unLocked, [=]() {
       // unlock event
     });
 
-    connect(lockWidget, &Lock::passwordSet, settingsWidget, [=]() {
-      if (settings.value("asdfg").isValid()) {
-        settingsWidget->setCurrentPasswordText(QByteArray::fromBase64(
-            settings.value("asdfg").toString().toUtf8()));
+    connect(m_lockWidget, &Lock::passwordSet, m_settingsWidget, [=]() {
+      if (SettingsManager::instance().settings().value("asdfg").isValid()) {
+        m_settingsWidget->setCurrentPasswordText(
+            QByteArray::fromBase64(SettingsManager::instance()
+                                       .settings()
+                                       .value("asdfg")
+                                       .toString()
+                                       .toUtf8()));
       } else {
-        settingsWidget->setCurrentPasswordText("Require setup");
+        m_settingsWidget->setCurrentPasswordText("Require setup");
       }
-      settingsWidget->appLockSetChecked(
-          settings.value("lockscreen", false).toBool());
+      m_settingsWidget->appLockSetChecked(SettingsManager::instance()
+                                              .settings()
+                                              .value("lockscreen", false)
+                                              .toBool());
     });
-    lockWidget->applyThemeQuirks();
+    m_lockWidget->applyThemeQuirks();
   }
 
-  lockWidget->setGeometry(this->rect());
+  m_lockWidget->setGeometry(this->rect());
 
-  if (settings.value("lockscreen").toBool()) {
-    if (settings.value("asdfg").isValid()) {
-      lockWidget->lock_app();
+  if (SettingsManager::instance().settings().value("lockscreen").toBool()) {
+    if (SettingsManager::instance().settings().value("asdfg").isValid()) {
+      m_lockWidget->lock_app();
     } else {
-      lockWidget->signUp();
+      m_lockWidget->signUp();
     }
-    lockWidget->show();
+    m_lockWidget->show();
   } else {
-    lockWidget->hide();
+    m_lockWidget->hide();
   }
   updateWindowTheme();
 }
 
 void MainWindow::changeLockPassword() {
-  settings.remove("asdfg");
-  settingsWidget->appLockSetChecked(false);
-  settingsWidget->autoAppLockSetChecked(false);
-  settingsWidget->updateAppLockPasswordViewer();
+  SettingsManager::instance().settings().remove("asdfg");
+  m_settingsWidget->appLockSetChecked(false);
+  m_settingsWidget->autoAppLockSetChecked(false);
+  m_settingsWidget->updateAppLockPasswordViewer();
   tryLogOut();
   QTimer::singleShot(1000, this, [=]() {
     if (isLoggedIn()) {
@@ -727,16 +726,22 @@ void MainWindow::changeLockPassword() {
 }
 
 void MainWindow::appAutoLockChanged() {
-  bool enabled = settings.value("appAutoLocking", defaultAppAutoLock).toBool();
+  bool enabled = SettingsManager::instance()
+                     .settings()
+                     .value("appAutoLocking", defaultAppAutoLock)
+                     .toBool();
   if (enabled) {
-    autoLockEventFilter->setTimeoutmillis(
-        settings.value("autoLockDuration", defaultAppAutoLockDuration).toInt() *
+    m_autoLockEventFilter->setTimeoutmillis(
+        SettingsManager::instance()
+            .settings()
+            .value("autoLockDuration", defaultAppAutoLockDuration)
+            .toInt() *
         1000);
-    qApp->installEventFilter(autoLockEventFilter);
-    autoLockEventFilter->resetTimer();
+    qApp->installEventFilter(m_autoLockEventFilter);
+    m_autoLockEventFilter->resetTimer();
   } else {
-    autoLockEventFilter->stopTimer();
-    qApp->removeEventFilter(autoLockEventFilter);
+    m_autoLockEventFilter->stopTimer();
+    qApp->removeEventFilter(m_autoLockEventFilter);
   }
 }
 
@@ -752,7 +757,7 @@ void MainWindow::checkWindowState() {
       menu->actions().at(0)->setDisabled(true);
       menu->actions().at(1)->setDisabled(false);
     }
-    if (lockWidget && lockWidget->getIsLocked()) {
+    if (m_lockWidget && m_lockWidget->getIsLocked()) {
       menu->actions().at(4)->setDisabled(true);
     } else {
       menu->actions().at(4)->setDisabled(false);
@@ -763,13 +768,21 @@ void MainWindow::checkWindowState() {
 void MainWindow::initGlobalWebProfile() {
 
   QWebEngineProfile *profile = QWebEngineProfile::defaultProfile();
-  profile->setHttpUserAgent(
-      settings.value("useragent", defaultUserAgentStr).toString());
+  profile->setHttpUserAgent(SettingsManager::instance()
+                                .settings()
+                                .value("useragent", defaultUserAgentStr)
+                                .toString());
 
   QStringList dict_names;
-  dict_names.append(settings.value("sc_dict", "en-US").toString());
-
-  profile->setSpellCheckEnabled(settings.value("sc_enabled", true).toBool());
+  dict_names.append(SettingsManager::instance()
+                        .settings()
+                        .value("sc_dict", "en-US")
+                        .toString());
+
+  profile->setSpellCheckEnabled(SettingsManager::instance()
+                                    .settings()
+                                    .value("sc_enabled", true)
+                                    .toBool());
   profile->setSpellCheckLanguages(dict_names);
 
   auto *webSettings = profile->settings();
@@ -794,7 +807,10 @@ void MainWindow::initGlobalWebProfile() {
   webSettings->setAttribute(QWebEngineSettings::JavascriptCanAccessClipboard,
                             true);
   webSettings->setAttribute(QWebEngineSettings::PlaybackRequiresUserGesture,
-                            settings.value("autoPlayMedia", false).toBool());
+                            SettingsManager::instance()
+                                .settings()
+                                .value("autoPlayMedia", false)
+                                .toBool());
 }
 
 void MainWindow::createWebEngine() {
@@ -806,18 +822,18 @@ void MainWindow::createWebEngine() {
   widgetSize.setHorizontalStretch(1);
   widgetSize.setVerticalStretch(1);
 
-  dictionaries = Dictionaries::GetDictionaries();
+  m_dictionaries = Dictionaries::GetDictionaries();
 
-  WebView *webEngineView = new WebView(this, dictionaries);
+  WebView *webEngineView = new WebView(this, m_dictionaries);
   setCentralWidget(webEngineView);
   webEngineView->setSizePolicy(widgetSize);
   webEngineView->show();
 
-  this->webEngine = webEngineView;
+  this->m_webEngine = webEngineView;
 
-  webEngineView->addAction(minimizeAction);
-  webEngineView->addAction(lockAction);
-  webEngineView->addAction(quitAction);
+  webEngineView->addAction(m_minimizeAction);
+  webEngineView->addAction(m_lockAction);
+  webEngineView->addAction(m_quitAction);
 
   createWebPage(false);
 }
@@ -834,55 +850,69 @@ const QIcon MainWindow::getTrayIcon(const int &notificationCount) const {
 }
 
 void MainWindow::createWebPage(bool offTheRecord) {
-  if (offTheRecord && !otrProfile) {
-    otrProfile.reset(new QWebEngineProfile);
+  if (offTheRecord && !m_otrProfile) {
+    m_otrProfile.reset(new QWebEngineProfile);
   }
   auto profile =
-      offTheRecord ? otrProfile.get() : QWebEngineProfile::defaultProfile();
+      offTheRecord ? m_otrProfile.get() : QWebEngineProfile::defaultProfile();
 
   QStringList dict_names;
-  dict_names.append(settings.value("sc_dict", "en-US").toString());
-
-  profile->setSpellCheckEnabled(settings.value("sc_enabled", true).toBool());
+  dict_names.append(SettingsManager::instance()
+                        .settings()
+                        .value("sc_dict", "en-US")
+                        .toString());
+
+  profile->setSpellCheckEnabled(SettingsManager::instance()
+                                    .settings()
+                                    .value("sc_enabled", true)
+                                    .toBool());
   profile->setSpellCheckLanguages(dict_names);
-  profile->setHttpUserAgent(
-      settings.value("useragent", defaultUserAgentStr).toString());
+  profile->setHttpUserAgent(SettingsManager::instance()
+                                .settings()
+                                .value("useragent", defaultUserAgentStr)
+                                .toString());
 
   setNotificationPresenter(profile);
 
-  QWebEnginePage *page = new WebEnginePage(profile, webEngine);
-  if (settings.value("windowTheme", "light").toString() == "dark") {
+  QWebEnginePage *page = new WebEnginePage(profile, m_webEngine);
+  if (SettingsManager::instance()
+          .settings()
+          .value("windowTheme", "light")
+          .toString() == "dark") {
     page->setBackgroundColor(QColor(17, 27, 33)); // whatsapp dark bg color
   } else {
     page->setBackgroundColor(QColor(240, 240, 240)); // whatsapp light bg color
   }
-  webEngine->setPage(page);
+  m_webEngine->setPage(page);
   // page should be set parent of profile to prevent
   // Release of profile requested but WebEnginePage still not deleted. Expect
   // troubles !
   profile->setParent(page);
-  auto randomValue = QRandomGenerator::global()->generateDouble() * 300;
+  auto randomValue = QRandomGenerator::global()->generateDouble() * 300.0;
   page->setUrl(
       QUrl("https://web.whatsapp.com?v=" + QString::number(randomValue)));
 
   connect(profile, &QWebEngineProfile::downloadRequested,
-          &downloadManagerWidget, &DownloadManagerWidget::downloadRequested);
+          &m_downloadManagerWidget, &DownloadManagerWidget::downloadRequested);
 
-  connect(page, SIGNAL(fullScreenRequested(QWebEngineFullScreenRequest)), this,
-          SLOT(fullScreenRequested(QWebEngineFullScreenRequest)));
+  connect(page, &QWebEnginePage::fullScreenRequested, this,
+          &MainWindow::fullScreenRequested);
 
-  double currentFactor = settings.value("zoomFactor", 1.0).toDouble();
-  webEngine->page()->setZoomFactor(currentFactor);
+  double currentFactor = SettingsManager::instance()
+                             .settings()
+                             .value("zoomFactor", 1.0)
+                             .toDouble();
+  m_webEngine->page()->setZoomFactor(currentFactor);
 }
 
 void MainWindow::setNotificationPresenter(QWebEngineProfile *profile) {
-  auto *op = webEngine->findChild<NotificationPopup *>("engineNotifier");
+  auto *op = m_webEngine->findChild<NotificationPopup *>("engineNotifier");
   if (op != nullptr) {
     op->close();
     op->deleteLater();
   }
 
-  auto popup = new NotificationPopup(webEngine);
+  auto popup = new NotificationPopup(m_webEngine);
   popup->setObjectName("engineNotifier");
   connect(popup, &NotificationPopup::notification_clicked, popup, [=]() {
     if (windowState().testFlag(Qt::WindowMinimized) ||
@@ -894,25 +924,36 @@ void MainWindow::setNotificationPresenter(QWebEngineProfile *profile) {
 
   profile->setNotificationPresenter(
       [=](std::unique_ptr<QWebEngineNotification> notification) {
-        if (settings.value("disableNotificationPopups", false).toBool() ==
-            true) {
+        if (SettingsManager::instance()
+                .settings()
+                .value("disableNotificationPopups", false)
+                .toBool() == true) {
           return;
         }
-        if (settings.value("notificationCombo", 1).toInt() == 0 &&
-            trayIcon != nullptr) {
+        if (SettingsManager::instance()
+                    .settings()
+                    .value("notificationCombo", 1)
+                    .toInt() == 0 &&
+            m_systemTrayIcon != nullptr) {
           QIcon icon(QPixmap::fromImage(notification->icon()));
-          trayIcon->showMessage(
-              notification->title(), notification->message(), icon,
-              settings.value("notificationTimeOut", 9000).toInt());
-          trayIcon->disconnect(trayIcon, SIGNAL(messageClicked()));
-          connect(trayIcon, &QSystemTrayIcon::messageClicked, trayIcon, [=]() {
-            if (windowState().testFlag(Qt::WindowMinimized) ||
-                !windowState().testFlag(Qt::WindowActive) || this->isHidden()) {
-              this->show();
-              setWindowState((windowState() & ~Qt::WindowMinimized) |
-                             Qt::WindowActive);
-            }
-          });
+          m_systemTrayIcon->showMessage(notification->title(),
+                                        notification->message(), icon,
+                                        SettingsManager::instance()
+                                            .settings()
+                                            .value("notificationTimeOut", 9000)
+                                            .toInt());
+          m_systemTrayIcon->disconnect(m_systemTrayIcon,
+                                       SIGNAL(messageClicked()));
+          connect(m_systemTrayIcon, &QSystemTrayIcon::messageClicked,
+                  m_systemTrayIcon, [=]() {
+                    if (windowState().testFlag(Qt::WindowMinimized) ||
+                        !windowState().testFlag(Qt::WindowActive) ||
+                        this->isHidden()) {
+                      this->show();
+                      setWindowState((windowState() & ~Qt::WindowMinimized) |
+                                     Qt::WindowActive);
+                    }
+                  });
 
         } else {
           popup->setMinimumWidth(300);
@@ -924,39 +965,39 @@ void MainWindow::setNotificationPresenter(QWebEngineProfile *profile) {
 
 void MainWindow::fullScreenRequested(QWebEngineFullScreenRequest request) {
   if (request.toggleOn()) {
-    webEngine->showFullScreen();
+    m_webEngine->showFullScreen();
     this->showFullScreen();
     request.accept();
   } else {
-    webEngine->showNormal();
+    m_webEngine->showNormal();
     this->show();
     request.accept();
   }
 }
 
-void MainWindow::handleWebViewTitleChanged(QString title) {
+void MainWindow::handleWebViewTitleChanged(const QString &title) {
   setWindowTitle(QApplication::applicationName() + ": " + title);
 
-  if (notificationsTitleRegExp.exactMatch(title)) {
-    if (notificationsTitleRegExp.capturedTexts().isEmpty() == false) {
-      QString capturedTitle =
-          notificationsTitleRegExp.capturedTexts().constFirst();
-      unreadMessageCountRegExp.setMinimal(true);
-      if (unreadMessageCountRegExp.indexIn(capturedTitle) != -1) {
-        QString unreadMessageCountStr =
-            unreadMessageCountRegExp.capturedTexts().constLast();
-        int unreadMessageCount = unreadMessageCountStr.toInt();
-
-        restoreAction->setText(
-            tr("Restore") + " | " + unreadMessageCountStr + " " +
-            (unreadMessageCount > 1 ? tr("messages") : tr("message")));
-        trayIcon->setIcon(getTrayIcon(unreadMessageCount));
-        setWindowIcon(getTrayIcon(unreadMessageCount));
-      }
+  QRegularExpressionMatch match = m_notificationsTitleRegExp.match(title);
+  if (match.hasMatch()) {
+    QString capturedTitle = match.captured(0);
+    m_unreadMessageCountRegExp.setPatternOptions(
+        QRegularExpression::DontCaptureOption);
+    QRegularExpressionMatch countMatch =
+        m_unreadMessageCountRegExp.match(capturedTitle);
+    if (countMatch.hasMatch()) {
+      QString unreadMessageCountStr = countMatch.captured(0);
+      int unreadMessageCount = unreadMessageCountStr.toInt();
+
+      m_restoreAction->setText(
+          tr("Restore") + " | " + unreadMessageCountStr + " " +
+          (unreadMessageCount > 1 ? tr("messages") : tr("message")));
+      m_systemTrayIcon->setIcon(getTrayIcon(unreadMessageCount));
+      setWindowIcon(getTrayIcon(unreadMessageCount));
     }
   } else {
-    trayIcon->setIcon(trayIconNormal);
-    setWindowIcon(trayIconNormal);
+    m_systemTrayIcon->setIcon(m_trayIconNormal);
+    setWindowIcon(m_trayIconNormal);
   }
 }
 
@@ -966,35 +1007,38 @@ void MainWindow::handleLoadFinished(bool loaded) {
     checkLoadedCorrectly();
     updatePageTheme();
     handleZoom();
-
-    if (settingsWidget != nullptr) {
-      settingsWidget->refresh();
+    if (m_settingsWidget != nullptr) {
+      m_settingsWidget->refresh();
     }
   }
 }
 
 void MainWindow::checkLoadedCorrectly() {
-  if (webEngine && webEngine->page()) {
+  if (m_webEngine && m_webEngine->page()) {
     // test 1 based on the class name of body tag of the page
-    webEngine->page()->runJavaScript(
+    m_webEngine->page()->runJavaScript(
         "document.querySelector('body').className",
         [this](const QVariant &result) {
           if (result.toString().contains("page-version", Qt::CaseInsensitive)) {
             qDebug() << "Test 1 found" << result.toString();
-            webEngine->page()->runJavaScript(
+            m_webEngine->page()->runJavaScript(
                 "document.getElementsByTagName('body')[0].innerText = ''");
             loadingQuirk("test1");
-          } else if (webEngine->title().contains("Error",
-                                                 Qt::CaseInsensitive)) {
-            utils::delete_cache(webEngine->page()->profile()->cachePath());
-            utils::delete_cache(
-                webEngine->page()->profile()->persistentStoragePath());
-            settings.setValue("useragent", defaultUserAgentStr);
-            utils::DisplayExceptionErrorDialog(
+          } else if (m_webEngine->title().contains("Error",
+                                                   Qt::CaseInsensitive)) {
+            Utils::delete_cache(m_webEngine->page()->profile()->cachePath());
+            Utils::delete_cache(
+                m_webEngine->page()->profile()->persistentStoragePath());
+            SettingsManager::instance().settings().setValue(
+                "useragent", defaultUserAgentStr);
+            Utils::DisplayExceptionErrorDialog(
                 "test1 handleWebViewTitleChanged(title) title: Error, "
                 "Resetting UA, Quiting!\nUA: " +
-                settings.value("useragent", "DefaultUA").toString());
-            quitAction->trigger();
+                SettingsManager::instance()
+                    .settings()
+                    .value("useragent", "DefaultUA")
+                    .toString());
+            m_quitAction->trigger();
           } else {
             qDebug() << "Test 1 loaded correctly, value:" << result.toString();
           }
@@ -1002,24 +1046,29 @@ void MainWindow::checkLoadedCorrectly() {
   }
 }
 
-void MainWindow::loadingQuirk(QString test) {
+void MainWindow::loadingQuirk(const QString &test) {
   // contains ug message apply quirk
-  if (correctlyLoaderRetries > -1) {
+  if (m_correctlyLoadedRetries > -1) {
     qWarning() << test << "checkLoadedCorrectly()/loadingQuirk()/doReload()"
-               << correctlyLoaderRetries;
+               << m_correctlyLoadedRetries;
     doReload(false, false, true);
-    correctlyLoaderRetries--;
+    m_correctlyLoadedRetries--;
   } else {
-    utils::delete_cache(webEngine->page()->profile()->cachePath());
-    utils::delete_cache(webEngine->page()->profile()->persistentStoragePath());
-    settings.setValue("useragent", defaultUserAgentStr);
-    utils::DisplayExceptionErrorDialog(
+    Utils::delete_cache(m_webEngine->page()->profile()->cachePath());
+    Utils::delete_cache(
+        m_webEngine->page()->profile()->persistentStoragePath());
+    SettingsManager::instance().settings().setValue("useragent",
+                                                    defaultUserAgentStr);
+    Utils::DisplayExceptionErrorDialog(
         test +
         " checkLoadedCorrectly()/loadingQuirk() reload retries 0, Resetting "
         "UA, Quiting!\nUA: " +
-        settings.value("useragent", "DefaultUA").toString());
+        SettingsManager::instance()
+            .settings()
+            .value("useragent", "DefaultUA")
+            .toString());
 
-    quitAction->trigger();
+    m_quitAction->trigger();
   }
 }
 
@@ -1027,8 +1076,10 @@ void MainWindow::loadingQuirk(QString test) {
 // manager
 void MainWindow::handleDownloadRequested(QWebEngineDownloadItem *download) {
   QFileDialog dialog(this);
-  bool usenativeFileDialog =
-      settings.value("useNativeFileDialog", false).toBool();
+  bool usenativeFileDialog = SettingsManager::instance()
+                                 .settings()
+                                 .value("useNativeFileDialog", false)
+                                 .toBool();
 
   if (usenativeFileDialog == false) {
     dialog.setOption(QFileDialog::DontUseNativeDialog, true);
@@ -1046,7 +1097,10 @@ void MainWindow::handleDownloadRequested(QWebEngineDownloadItem *download) {
 }
 
 void MainWindow::iconActivated(QSystemTrayIcon::ActivationReason reason) {
-  if (settings.value("minimizeOnTrayIconClick", false).toBool() == false ||
+  if (SettingsManager::instance()
+              .settings()
+              .value("minimizeOnTrayIconClick", false)
+              .toBool() == false ||
       reason == QSystemTrayIcon::Context)
     return;
   if (isVisible()) {
@@ -1066,8 +1120,8 @@ void MainWindow::messageClicked() {
 
 void MainWindow::doAppReload() {
 
-  if (webEngine->page()) {
-    webEngine->page()->disconnect();
+  if (m_webEngine->page()) {
+    m_webEngine->page()->disconnect();
   }
   createWebPage(false);
 }
@@ -1083,13 +1137,13 @@ void MainWindow::newChat() {
   }
 }
 
-void MainWindow::triggerNewChat(QString phone, QString text) {
+void MainWindow::triggerNewChat(const QString &phone, const QString &text) {
   static QString phoneStr, textStr;
-  webEngine->page()->runJavaScript(
+  m_webEngine->page()->runJavaScript(
       "openNewChatWhatsieDefined()",
       [this, phone, text](const QVariant &result) {
         if (result.toString().contains("true")) {
-          webEngine->page()->runJavaScript(
+          m_webEngine->page()->runJavaScript(
               QString("openNewChatWhatsie(\"%1\",\"%2\")").arg(phone, text));
         } else {
           // create send url equivalent
@@ -1097,7 +1151,7 @@ void MainWindow::triggerNewChat(QString phone, QString text) {
           textStr = text.isEmpty() ? "" : "text=" + text;
           QString urlStr =
               "https://web.whatsapp.com/send?" + phoneStr + "&" + textStr;
-          webEngine->page()->load(QUrl(urlStr));
+          m_webEngine->page()->load(QUrl(urlStr));
         }
         this->alreadyRunning();
       });
@@ -1106,10 +1160,10 @@ void MainWindow::triggerNewChat(QString phone, QString text) {
 void MainWindow::doReload(bool byPassCache, bool isAskedByCLI,
                           bool byLoadingQuirk) {
   if (byLoadingQuirk) {
-    webEngine->triggerPageAction(QWebEnginePage::ReloadAndBypassCache,
-                                 byPassCache);
+    m_webEngine->triggerPageAction(QWebEnginePage::ReloadAndBypassCache,
+                                   byPassCache);
   } else {
-    if (lockWidget && !lockWidget->getIsLocked()) {
+    if (m_lockWidget && !m_lockWidget->getIsLocked()) {
       this->notify(QApplication::applicationName(),
                    QObject::tr("Reloading..."));
     } else {
@@ -1123,40 +1177,41 @@ void MainWindow::doReload(bool byPassCache, bool isAskedByCLI,
       this->show();
       return;
     }
-    webEngine->triggerPageAction(QWebEnginePage::ReloadAndBypassCache,
-                                 byPassCache);
+    m_webEngine->triggerPageAction(QWebEnginePage::ReloadAndBypassCache,
+                                   byPassCache);
   }
 }
 
 void MainWindow::toggleMute(const bool &checked) {
-  webEngine->page()->setAudioMuted(checked);
+  m_webEngine->page()->setAudioMuted(checked);
 }
 
 // get value of page theme when page is loaded
-QString MainWindow::getPageTheme() {
+QString MainWindow::getPageTheme() const {
   static QString theme = "web"; // implies light
-  if (webEngine && webEngine->page()) {
-    webEngine->page()->runJavaScript(
+  if (m_webEngine && m_webEngine->page()) {
+    m_webEngine->page()->runJavaScript(
         "document.querySelector('body').className;",
-        [this](const QVariant &result) {
+        [=](const QVariant &result) {
           theme = result.toString();
           theme.contains("dark") ? theme = "dark" : theme = "light";
-          settings.setValue("windowTheme", theme);
+          SettingsManager::instance().settings().setValue("windowTheme", theme);
         });
   }
   return theme;
 }
 
 void MainWindow::tryLock() {
-  if (settings.value("asdfg").isValid()) {
+  if (SettingsManager::instance().settings().value("asdfg").isValid()) {
     initLock();
     return;
   }
-  if (settings.value("asdfg").isValid() == false) {
-    settings.setValue("lockscreen", false);
-    settings.setValue("appAutoLocking", false);
-    settingsWidget->appAutoLockingSetChecked(false);
-    settingsWidget->appLockSetChecked(false);
+  if (SettingsManager::instance().settings().value("asdfg").isValid() ==
+      false) {
+    SettingsManager::instance().settings().setValue("lockscreen", false);
+    SettingsManager::instance().settings().setValue("appAutoLocking", false);
+    m_settingsWidget->appAutoLockingSetChecked(false);
+    m_settingsWidget->appLockSetChecked(false);
     initLock();
   }
 }
diff --git a/src/mainwindow.h b/src/mainwindow.h
index 4ca25d5..c5e2821 100644
--- a/src/mainwindow.h
+++ b/src/mainwindow.h
@@ -11,8 +11,6 @@
 #include <QMessageBox>
 #include <QProgressBar>
 #include <QRadioButton>
-#include <QRegExp>
-#include <QSettings>
 #include <QStatusBar>
 #include <QStyle>
 #include <QStyleFactory>
@@ -33,6 +31,7 @@
 #include "rateapp.h"
 #include "requestinterceptor.h"
 #include "settingswidget.h"
+#include "theme.h"
 #include "webenginepage.h"
 #include "webview.h"
 
@@ -42,23 +41,25 @@ public:
   explicit MainWindow(QWidget *parent = nullptr);
   ~MainWindow();
 
+  void loadSchemaUrl(const QString &arg);
+  void alreadyRunning(bool notify = false);
+  void runMinimized();
+  void notify(QString title, QString message);
+  void doReload(bool byPassCache = false, bool isAskedByCLI = false,
+                bool byLoadingQuirk = false);
+
 public slots:
   void updateWindowTheme();
   void updatePageTheme();
-  void handleWebViewTitleChanged(QString title);
+  void handleWebViewTitleChanged(const QString &title);
   void handleLoadFinished(bool loaded);
   void handleDownloadRequested(QWebEngineDownloadItem *download);
-  void loadSchemaUrl(const QString &arg);
   void showSettings(bool isAskedByCLI = false);
   void showAbout();
   void lockApp();
-  void runMinimized();
-  void alreadyRunning(bool notify = false);
-  void notify(QString title, QString message);
   void toggleTheme();
-  void doReload(bool byPassCache = false, bool isAskedByCLI = false,
-                bool byLoadingQuirk = false);
   void newChat();
+
 protected slots:
   void closeEvent(QCloseEvent *event) override;
   void resizeEvent(QResizeEvent *event) override;
@@ -66,71 +67,67 @@ protected slots:
 
 private:
   const QIcon getTrayIcon(const int &notificationCount) const;
-  QPalette lightPalette, darkPalette;
   void createActions();
   void createTrayIcon();
   void createWebEngine();
-
-  QSettings settings;
-  QRegExp notificationsTitleRegExp;
-  QIcon trayIconNormal;
-  QRegExp unreadMessageCountRegExp;
-
-  QAction *reloadAction;
-  QAction *minimizeAction;
-  QAction *restoreAction;
-  QAction *aboutAction;
-  QAction *settingsAction;
-  QAction *toggleThemeAction;
-  QAction *quitAction;
-  QAction *lockAction;
-  QAction *fullscreenAction;
-  QAction *openUrlAction;
-
-  QMenu *trayIconMenu;
-  QSystemTrayIcon *trayIcon;
-  QWebEngineView *webEngine;
-  SettingsWidget *settingsWidget = nullptr;
-  DownloadManagerWidget downloadManagerWidget;
-  QScopedPointer<QWebEngineProfile> otrProfile;
-  Lock *lockWidget = nullptr;
-  int correctlyLoaderRetries = 4;
-  QStringList dictionaries;
-  AutoLockEventFilter *autoLockEventFilter = nullptr;
-
-private slots:
-
-  QString getPageTheme();
-  void iconActivated(QSystemTrayIcon::ActivationReason reason);
-  void messageClicked();
+  QString getPageTheme() const;
   void handleCookieAdded(const QNetworkCookie &cookie);
-  void toggleMute(const bool &checked);
   void doAppReload();
   void askToReloadPage();
   void updateSettingsUserAgentWidget();
-  void fullScreenRequested(QWebEngineFullScreenRequest request);
   void createWebPage(bool offTheRecord = false);
   void initSettingWidget();
   void initGlobalWebProfile();
-  void checkWindowState();
-  void initLock();
   void tryLock();
   void checkLoadedCorrectly();
-  void loadingQuirk(QString test);
+  void loadingQuirk(const QString &test);
   void setNotificationPresenter(QWebEngineProfile *profile);
-  void quitApp();
   void initRateWidget();
-  void initThemes();
   void handleZoomOnWindowStateChange(const QWindowStateChangeEvent *ev);
   void handleZoom();
-  void changeLockPassword();
   void forceLogOut();
-  void tryLogOut();
   bool isLoggedIn();
+  void tryLogOut();
   void initAutoLock();
-  void appAutoLockChanged();
-  void triggerNewChat(QString phone, QString text);
+  void triggerNewChat(const QString &phone, const QString &text);
   void restoreMainWindow();
+
+  QIcon m_trayIconNormal;
+  QRegularExpression m_notificationsTitleRegExp;
+  QRegularExpression m_unreadMessageCountRegExp;
+  DownloadManagerWidget m_downloadManagerWidget;
+  QScopedPointer<QWebEngineProfile> m_otrProfile;
+  int m_correctlyLoadedRetries = 4;
+  QStringList m_dictionaries;
+
+  QAction *m_reloadAction = nullptr;
+  QAction *m_minimizeAction = nullptr;
+  QAction *m_restoreAction = nullptr;
+  QAction *m_aboutAction = nullptr;
+  QAction *m_settingsAction = nullptr;
+  QAction *m_toggleThemeAction = nullptr;
+  QAction *m_quitAction = nullptr;
+  QAction *m_lockAction = nullptr;
+  QAction *m_fullscreenAction = nullptr;
+  QAction *m_openUrlAction = nullptr;
+
+  QMenu *m_trayIconMenu = nullptr;
+  QSystemTrayIcon *m_systemTrayIcon = nullptr;
+  QWebEngineView *m_webEngine = nullptr;
+  SettingsWidget *m_settingsWidget = nullptr;
+  Lock *m_lockWidget = nullptr;
+  AutoLockEventFilter *m_autoLockEventFilter = nullptr;
+
+private slots:
+  void iconActivated(QSystemTrayIcon::ActivationReason reason);
+  void messageClicked();
+  void toggleMute(const bool &checked);
+  void fullScreenRequested(QWebEngineFullScreenRequest request);
+  void checkWindowState();
+  void initLock();
+  void quitApp();
+  void changeLockPassword();
+  void appAutoLockChanged();
 };
 
 #endif // MAINWINDOW_H
diff --git a/src/notificationpopup.h b/src/notificationpopup.h
index 3a765e0..69aa478 100644
--- a/src/notificationpopup.h
+++ b/src/notificationpopup.h
@@ -1,9 +1,9 @@
 #ifndef NOTIFICATIONPOPUP_H
 #define NOTIFICATIONPOPUP_H
 
-#pragma once
-
+#include "settingsmanager.h"
 #include "widgets/scrolltext/scrolltext.h"
+
 #include <QApplication>
 #include <QDebug>
 #include <QDesktopWidget>
@@ -13,7 +13,6 @@
 #include <QPropertyAnimation>
 #include <QPushButton>
 #include <QScreen>
-#include <QSettings>
 #include <QSpacerItem>
 #include <QTimer>
 #include <QVBoxLayout>
@@ -27,7 +26,6 @@ class NotificationPopup : public QWidget {
   QLabel m_icon, m_title;
   ScrollText m_message;
   std::unique_ptr<QWebEngineNotification> notification;
-  QSettings settings;
 
 public:
   NotificationPopup(QWidget *parent) : QWidget(parent) {
@@ -62,7 +60,10 @@ public:
         image.scaledToHeight(m_icon.height(), Qt::SmoothTransformation));
     this->adjustSize();
 
-    QTimer::singleShot(settings.value("notificationTimeOut", 9000).toInt(),
+    QTimer::singleShot(SettingsManager::instance()
+                           .settings()
+                           .value("notificationTimeOut", 9000)
+                           .toInt(),
                        this, [=]() { onClosed(); });
 
     animateIn(screenNumber);
@@ -87,7 +88,10 @@ public:
 
     connect(notification.get(), &QWebEngineNotification::closed, this,
             &NotificationPopup::onClosed);
-    QTimer::singleShot(settings.value("notificationTimeOut", 9000).toInt(),
+    QTimer::singleShot(SettingsManager::instance()
+                           .settings()
+                           .value("notificationTimeOut", 9000)
+                           .toInt(),
                        notification.get(), [&]() { onClosed(); });
 
     animateIn(screenNumber);
diff --git a/src/permissiondialog.cpp b/src/permissiondialog.cpp
index c0eeac6..7ca9a4d 100644
--- a/src/permissiondialog.cpp
+++ b/src/permissiondialog.cpp
@@ -1,9 +1,6 @@
 #include "permissiondialog.h"
 #include "ui_permissiondialog.h"
 
-#include <QCheckBox>
-#include <QMetaEnum>
-#include <QWebEnginePage>
 
 PermissionDialog::PermissionDialog(QWidget *parent)
     : QWidget(parent), ui(new Ui::PermissionDialog) {
@@ -41,7 +38,7 @@ void PermissionDialog::addToFeaturesTable(QWebEnginePage::Feature feature,
 
     // insertRow
     ui->featuresTableWidget->insertRow(nextRow);
-    settings.beginGroup("permissions");
+    SettingsManager::instance().settings().beginGroup("permissions");
     // add column
     for (int i = 0; i < columnData.count(); i++) {
 
@@ -50,10 +47,10 @@ void PermissionDialog::addToFeaturesTable(QWebEnginePage::Feature feature,
         featureCheckBox->setStyleSheet(
             "border:0px;margin-left:50%; margin-right:50%;");
         featureCheckBox->setChecked(
-            settings.value(featureName, false).toBool());
+            SettingsManager::instance().settings().value(featureName, false).toBool());
         connect(featureCheckBox, &QCheckBox::toggled, [=](bool checked) {
           // save permission
-          settings.setValue("permissions/" + featureName, checked);
+          SettingsManager::instance().settings().setValue("permissions/" + featureName, checked);
           emit webPageFeatureChanged(feature);
         });
         ui->featuresTableWidget->setCellWidget(nextRow, i, featureCheckBox);
@@ -65,7 +62,7 @@ void PermissionDialog::addToFeaturesTable(QWebEnginePage::Feature feature,
       }
       this->update();
     }
-    settings.endGroup();
+    SettingsManager::instance().settings().endGroup();
   }
 }
 
diff --git a/src/permissiondialog.h b/src/permissiondialog.h
index 2460a2d..0baf406 100644
--- a/src/permissiondialog.h
+++ b/src/permissiondialog.h
@@ -1,10 +1,13 @@
 #ifndef PERMISSIONDIALOG_H
 #define PERMISSIONDIALOG_H
 
-#include <QSettings>
+#include <QCheckBox>
+#include <QKeyEvent>
+#include <QMetaEnum>
 #include <QWebEnginePage>
 #include <QWidget>
-#include <QKeyEvent>
+
+#include "settingsmanager.h"
 
 namespace Ui {
 class PermissionDialog;
@@ -22,13 +25,13 @@ signals:
 
 protected slots:
   void keyPressEvent(QKeyEvent *e);
+
 private slots:
   void addToFeaturesTable(QWebEnginePage::Feature feature,
                           QString &featureName);
 
 private:
   Ui::PermissionDialog *ui;
-  QSettings settings;
 };
 
 #endif // PERMISSIONDIALOG_H
diff --git a/src/rateapp.cpp b/src/rateapp.cpp
index 5c370a9..c258c37 100644
--- a/src/rateapp.cpp
+++ b/src/rateapp.cpp
@@ -22,7 +22,7 @@ RateApp::RateApp(QWidget *parent, QString app_rating_url, int app_launch_count,
 
   showTimer = new QTimer(this);
   showTimer->setInterval(this->present_delay);
-  connect(showTimer, &QTimer::timeout, [=]() {
+  connect(showTimer, &QTimer::timeout, this, [=]() {
     qDebug() << "Rate timer timeout";
     emit showRateDialog();
     if (this->isVisible())
@@ -30,15 +30,26 @@ RateApp::RateApp(QWidget *parent, QString app_rating_url, int app_launch_count,
   });
 
   // increase the app_launched_count by one
-  int app_launched = settings.value("app_launched_count", 0).toInt();
-  settings.setValue("app_launched_count", app_launched + 1);
+  int app_launched = SettingsManager::instance()
+                         .settings()
+                         .value("app_launched_count", 0)
+                         .toInt();
+  SettingsManager::instance().settings().setValue("app_launched_count",
+                                                  app_launched + 1);
 
   // check if app install time is set in settings
-  if (settings.value("app_install_time").isNull()) {
-    settings.setValue("app_install_time", QDateTime::currentSecsSinceEpoch());
-
-  } else if (settings.value("app_install_time").isValid()) {
-    //qDebug() << "RATEAPP should show:" << shouldShow();
+  if (SettingsManager::instance()
+          .settings()
+          .value("app_install_time")
+          .isNull()) {
+    SettingsManager::instance().settings().setValue(
+        "app_install_time", QDateTime::currentSecsSinceEpoch());
+
+  } else if (SettingsManager::instance()
+                 .settings()
+                 .value("app_install_time")
+                 .isValid()) {
+    // qDebug() << "RATEAPP should show:" << shouldShow();
     if (shouldShow()) {
       showTimer->start();
     } else {
@@ -49,7 +60,10 @@ RateApp::RateApp(QWidget *parent, QString app_rating_url, int app_launch_count,
   }
 
   // if already reated delete this obj to free resources
-  if (settings.value("rated_already", false).toBool()) {
+  if (SettingsManager::instance()
+          .settings()
+          .value("rated_already", false)
+          .toBool()) {
     this->deleteLater();
   }
 }
@@ -70,10 +84,19 @@ void RateApp::delayShowEvent() {
  */
 bool RateApp::shouldShow() {
   bool shouldShow = false;
-  int app_launched_count = settings.value("app_launched_count", 0).toInt();
+  int app_launched_count = SettingsManager::instance()
+                               .settings()
+                               .value("app_launched_count", 0)
+                               .toInt();
   qint64 currentDateTime = QDateTime::currentSecsSinceEpoch();
-  qint64 installed_date_time = settings.value("app_install_time").toLongLong();
-  bool ratedAlready = settings.value("rated_already", false).toBool();
+  qint64 installed_date_time = SettingsManager::instance()
+                                   .settings()
+                                   .value("app_install_time")
+                                   .toLongLong();
+  bool ratedAlready = SettingsManager::instance()
+                          .settings()
+                          .value("rated_already", false)
+                          .toBool();
 
   if (ratedAlready) // return false if already reated;
     return false;
@@ -99,7 +122,7 @@ void RateApp::on_rateNowBtn_clicked() {
 }
 
 void RateApp::on_alreadyDoneBtn_clicked() {
-  settings.setValue("rated_already", true);
+  SettingsManager::instance().settings().setValue("rated_already", true);
   this->close();
 }
 
@@ -109,9 +132,10 @@ void RateApp::on_laterBtn_clicked() {
 }
 
 void RateApp::reset() {
-  settings.setValue("rated_already", false);
-  settings.setValue("app_launched_count", 0);
-  settings.setValue("app_install_time", QDateTime::currentSecsSinceEpoch());
+  SettingsManager::instance().settings().setValue("rated_already", false);
+  SettingsManager::instance().settings().setValue("app_launched_count", 0);
+  SettingsManager::instance().settings().setValue(
+      "app_install_time", QDateTime::currentSecsSinceEpoch());
 }
 
 void RateApp::on_rateOnGithub_clicked() {
diff --git a/src/rateapp.h b/src/rateapp.h
index 50d5b98..ffb601c 100644
--- a/src/rateapp.h
+++ b/src/rateapp.h
@@ -1,55 +1,55 @@
 #ifndef RATEAPP_H
 #define RATEAPP_H
 
-#include <QWidget>
-#include <QSettings>
 #include <QDateTime>
-#include <QUrl>
 #include <QDesktopServices>
 #include <QTimer>
+#include <QUrl>
+#include <QWidget>
+
+#include "settingsmanager.h"
 
 namespace Ui {
 class RateApp;
 }
 
-class RateApp : public QWidget
-{
-    Q_OBJECT
+class RateApp : public QWidget {
+  Q_OBJECT
 
 signals:
-    void showRateDialog();
+  void showRateDialog();
 
 public:
-    explicit RateApp(QWidget *parent = nullptr , QString app_rating_url = "",
-                     int app_launch_count = 5, int app_install_days = 5, int present_delay = 5000);
-    ~RateApp();
+  explicit RateApp(QWidget *parent = nullptr, QString app_rating_url = "",
+                   int app_launch_count = 5, int app_install_days = 5,
+                   int present_delay = 5000);
+  ~RateApp();
 
 public slots:
-    void delayShowEvent();
+  void delayShowEvent();
 
 private slots:
-    void on_rateNowBtn_clicked();
+  void on_rateNowBtn_clicked();
 
-    void on_alreadyDoneBtn_clicked();
+  void on_alreadyDoneBtn_clicked();
 
-    void on_laterBtn_clicked();
+  void on_laterBtn_clicked();
 
-    bool shouldShow();
-    void reset();
-    void on_rateOnGithub_clicked();
+  bool shouldShow();
+  void reset();
+  void on_rateOnGithub_clicked();
 
-    void on_donate_clicked();
+  void on_donate_clicked();
 
-    void on_donate_2_clicked();
+  void on_donate_2_clicked();
 
 private:
-    Ui::RateApp *ui;
-    QString app_rating_url;
-    int app_launch_count;
-    int app_install_days;
-    int present_delay;
-    QSettings settings;
-    QTimer *showTimer;
+  Ui::RateApp *ui;
+  QString app_rating_url;
+  int app_launch_count;
+  int app_install_days;
+  int present_delay;
+  QTimer *showTimer;
 };
 
 #endif // RATEAPP_H
diff --git a/src/requestinterceptor.h b/src/requestinterceptor.h
index 95f2d48..8d8f261 100644
--- a/src/requestinterceptor.h
+++ b/src/requestinterceptor.h
@@ -1,41 +1,39 @@
 #ifndef REQUESTINTERCEPTOR_H
 #define REQUESTINTERCEPTOR_H
-#include <QWebEnginePage>
+
+#include <QApplication>
 #include <QDebug>
 #include <QObject>
-#include <QWebEngineView>
-#include <QApplication>
+#include <QWebEnginePage>
 #include <QWebEngineUrlRequestInfo>
 #include <QWebEngineUrlRequestInterceptor>
-#include <QSettings>
+#include <QWebEngineView>
+
+#include "settingsmanager.h"
 
-class RequestInterceptor : public QWebEngineUrlRequestInterceptor
-{
-    Q_OBJECT
+class RequestInterceptor : public QWebEngineUrlRequestInterceptor {
+  Q_OBJECT
 
 signals:
-    void blocked(QString adUrl);
-private:
-    QSettings m_settings;
+  void blocked(QString adUrl);
 
 public:
-    RequestInterceptor(QObject *parent = nullptr) : QWebEngineUrlRequestInterceptor(parent)
-    {
-    }
+  RequestInterceptor(QObject *parent = nullptr)
+      : QWebEngineUrlRequestInterceptor(parent) {}
 
-    void interceptRequest(QWebEngineUrlRequestInfo &info)
-    {
-        QString reqUrlStr = info.requestUrl().toString();
+  void interceptRequest(QWebEngineUrlRequestInfo &info) {
+    QString reqUrlStr = info.requestUrl().toString();
 
-//        if(reqUrlStr.contains("mms-type=video")|| reqUrlStr.contains("stream/video?key")){
-//            if(m_settings.value("disableVideos",false).toBool()){
-//                info.block(true);
-//                qDebug()<<"INTERCEPTOR: Blocked video - "<<reqUrlStr;
-//            }
-//        }else{
-//            qDebug()<<"INTERCEPTOR:"<<reqUrlStr;
-//        }
-        qDebug()<<"INTERCEPTOR:"<<reqUrlStr;
-    }
+    //        if(reqUrlStr.contains("mms-type=video")||
+    //        reqUrlStr.contains("stream/video?key")){
+    //            if(SettingsManager::instance().settings().value("disableVideos",false).toBool()){
+    //                info.block(true);
+    //                qDebug()<<"INTERCEPTOR: Blocked video - "<<reqUrlStr;
+    //            }
+    //        }else{
+    //            qDebug()<<"INTERCEPTOR:"<<reqUrlStr;
+    //        }
+    qDebug() << "INTERCEPTOR:" << reqUrlStr;
+  }
 };
 #endif // REQUESTINTERCEPTOR_H
diff --git a/src/settingsmanager.h b/src/settingsmanager.h
new file mode 100644
index 0000000..2dc7c57
--- /dev/null
+++ b/src/settingsmanager.h
@@ -0,0 +1,21 @@
+#ifndef SETTINGSMANAGER_H
+#define SETTINGSMANAGER_H
+
+#include <QSettings>
+
+class SettingsManager {
+public:
+  static SettingsManager &instance() {
+    static SettingsManager instance;
+    return instance;
+  }
+
+  QSettings &settings() { return m_settings; }
+
+private:
+  SettingsManager() {}
+
+  QSettings m_settings;
+};
+
+#endif // SETTINGSMANAGER_H
diff --git a/src/settingswidget.cpp b/src/settingswidget.cpp
index 4bd213d..87f6d4c 100644
--- a/src/settingswidget.cpp
+++ b/src/settingswidget.cpp
@@ -23,48 +23,91 @@ SettingsWidget::SettingsWidget(QWidget *parent, int screenNumber,
   this->enginePersistentStoragePath = enginePersistentStoragePath;
 
   ui->zoomFactorSpinBox->setRange(0.25, 5.0);
-  ui->zoomFactorSpinBox->setValue(settings.value("zoomFactor", 1.0).toDouble());
+  ui->zoomFactorSpinBox->setValue(SettingsManager::instance()
+                                      .settings()
+                                      .value("zoomFactor", 1.0)
+                                      .toDouble());
 
   ui->zoomFactorSpinBoxMaximized->setRange(0.25, 5.0);
   ui->zoomFactorSpinBoxMaximized->setValue(
-      settings.value("zoomFactorMaximized", defaultZoomFactorMaximized)
+      SettingsManager::instance()
+          .settings()
+          .value("zoomFactorMaximized", defaultZoomFactorMaximized)
           .toDouble());
 
   ui->closeButtonActionComboBox->setCurrentIndex(
-      settings.value("closeButtonActionCombo", 0).toInt());
+      SettingsManager::instance()
+          .settings()
+          .value("closeButtonActionCombo", 0)
+          .toInt());
   ui->notificationCheckBox->setChecked(
-      settings.value("disableNotificationPopups", false).toBool());
-  ui->muteAudioCheckBox->setChecked(
-      settings.value("muteAudio", false).toBool());
-  ui->autoPlayMediaCheckBox->setChecked(
-      settings.value("autoPlayMedia", false).toBool());
+      SettingsManager::instance()
+          .settings()
+          .value("disableNotificationPopups", false)
+          .toBool());
+  ui->muteAudioCheckBox->setChecked(SettingsManager::instance()
+                                        .settings()
+                                        .value("muteAudio", false)
+                                        .toBool());
+  ui->autoPlayMediaCheckBox->setChecked(SettingsManager::instance()
+                                            .settings()
+                                            .value("autoPlayMedia", false)
+                                            .toBool());
   ui->themeComboBox->setCurrentText(
-      utils::toCamelCase(settings.value("windowTheme", "light").toString()));
-
-  ui->userAgentLineEdit->setText(
-      settings.value("useragent", defaultUserAgentStr).toString());
+      Utils::toCamelCase(SettingsManager::instance()
+                             .settings()
+                             .value("windowTheme", "light")
+                             .toString()));
+
+  ui->userAgentLineEdit->setText(SettingsManager::instance()
+                                     .settings()
+                                     .value("useragent", defaultUserAgentStr)
+                                     .toString());
   ui->userAgentLineEdit->home(true);
   ui->userAgentLineEdit->deselect();
 
-  ui->enableSpellCheck->setChecked(settings.value("sc_enabled", true).toBool());
+  ui->enableSpellCheck->setChecked(SettingsManager::instance()
+                                       .settings()
+                                       .value("sc_enabled", true)
+                                       .toBool());
   ui->notificationTimeOutspinBox->setValue(
-      settings.value("notificationTimeOut", 9000).toInt() / 1000);
-  ui->notificationCombo->setCurrentIndex(
-      settings.value("notificationCombo", 1).toInt());
-  ui->useNativeFileDialog->setChecked(
-      settings.value("useNativeFileDialog", false).toBool());
-  ui->startMinimized->setChecked(
-      settings.value("startMinimized", false).toBool());
+      SettingsManager::instance()
+          .settings()
+          .value("notificationTimeOut", 9000)
+          .toInt() /
+      1000);
+  ui->notificationCombo->setCurrentIndex(SettingsManager::instance()
+                                             .settings()
+                                             .value("notificationCombo", 1)
+                                             .toInt());
+  ui->useNativeFileDialog->setChecked(SettingsManager::instance()
+                                          .settings()
+                                          .value("useNativeFileDialog", false)
+                                          .toBool());
+  ui->startMinimized->setChecked(SettingsManager::instance()
+                                     .settings()
+                                     .value("startMinimized", false)
+                                     .toBool());
 
   this->appAutoLockingSetChecked(
-      settings.value("appAutoLocking", defaultAppAutoLock).toBool());
+      SettingsManager::instance()
+          .settings()
+          .value("appAutoLocking", defaultAppAutoLock)
+          .toBool());
 
   ui->autoLockDurationSpinbox->setValue(
-      settings.value("autoLockDuration", defaultAppAutoLockDuration).toInt());
+      SettingsManager::instance()
+          .settings()
+          .value("autoLockDuration", defaultAppAutoLockDuration)
+          .toInt());
   ui->minimizeOnTrayIconClick->setChecked(
-      settings.value("minimizeOnTrayIconClick", false).toBool());
+      SettingsManager::instance()
+          .settings()
+          .value("minimizeOnTrayIconClick", false)
+          .toBool());
   ui->defaultDownloadLocation->setText(
-      settings
+      SettingsManager::instance()
+          .settings()
           .value("defaultDownloadLocation",
                  QStandardPaths::writableLocation(
                      QStandardPaths::DownloadLocation) +
@@ -74,23 +117,29 @@ SettingsWidget::SettingsWidget(QWidget *parent, int screenNumber,
   ui->styleComboBox->blockSignals(true);
   ui->styleComboBox->addItems(QStyleFactory::keys());
   ui->styleComboBox->blockSignals(false);
-  ui->styleComboBox->setCurrentText(
-      settings.value("widgetStyle", "Fusion").toString());
+  ui->styleComboBox->setCurrentText(SettingsManager::instance()
+                                        .settings()
+                                        .value("widgetStyle", "Fusion")
+                                        .toString());
 
   ui->fullWidthViewCheckbox->blockSignals(true);
-  ui->fullWidthViewCheckbox->setChecked(
-      settings.value("fullWidthView", true).toBool());
+  ui->fullWidthViewCheckbox->setChecked(SettingsManager::instance()
+                                            .settings()
+                                            .value("fullWidthView", true)
+                                            .toBool());
   ui->fullWidthViewCheckbox->blockSignals(false);
 
   ui->automaticThemeCheckBox->blockSignals(true);
-  bool automaticThemeSwitching =
-      settings.value("automaticTheme", false).toBool();
+  bool automaticThemeSwitching = SettingsManager::instance()
+                                     .settings()
+                                     .value("automaticTheme", false)
+                                     .toBool();
   ui->automaticThemeCheckBox->setChecked(automaticThemeSwitching);
   ui->automaticThemeCheckBox->blockSignals(false);
 
   themeSwitchTimer = new QTimer(this);
   themeSwitchTimer->setInterval(60000); // 1 min
-  connect(themeSwitchTimer, &QTimer::timeout, &settings,
+  connect(themeSwitchTimer, &QTimer::timeout, this,
           [=]() { themeSwitchTimerTimeout(); });
 
   // instantly call the timeout slot if automatic theme switching enabled
@@ -100,7 +149,11 @@ SettingsWidget::SettingsWidget(QWidget *parent, int screenNumber,
   updateAutomaticTheme();
 
   this->setCurrentPasswordText(
-      QByteArray::fromBase64(settings.value("asdfg").toString().toUtf8()));
+      QByteArray::fromBase64(SettingsManager::instance()
+                                 .settings()
+                                 .value("asdfg")
+                                 .toString()
+                                 .toUtf8()));
 
   applyThemeQuirks();
 
@@ -124,8 +177,11 @@ SettingsWidget::SettingsWidget(QWidget *parent, int screenNumber,
   ui->scrollArea->setMinimumWidth(
       ui->groupBox_8->sizeHint().width() + ui->scrollArea->sizeHint().width() +
       ui->scrollAreaWidgetContents->layout()->spacing());
-  if (settings.value("settingsGeo").isValid()) {
-    this->restoreGeometry(settings.value("settingsGeo").toByteArray());
+  if (SettingsManager::instance().settings().value("settingsGeo").isValid()) {
+    this->restoreGeometry(SettingsManager::instance()
+                              .settings()
+                              .value("settingsGeo")
+                              .toByteArray());
     QRect screenRect = QGuiApplication::screens().at(screenNumber)->geometry();
     if (!screenRect.contains(this->pos())) {
       this->move(screenRect.center() - this->rect().center());
@@ -144,7 +200,8 @@ bool SettingsWidget::eventFilter(QObject *obj, QEvent *event) {
 }
 
 void SettingsWidget::closeEvent(QCloseEvent *event) {
-  settings.setValue("settingsGeo", this->saveGeometry());
+  SettingsManager::instance().settings().setValue("settingsGeo",
+                                                  this->saveGeometry());
   QWidget::closeEvent(event);
 }
 
@@ -161,13 +218,18 @@ inline bool inRange(unsigned low, unsigned high, unsigned x) {
 }
 
 void SettingsWidget::themeSwitchTimerTimeout() {
-  if (settings.value("automaticTheme", false).toBool()) {
+  if (SettingsManager::instance()
+          .settings()
+          .value("automaticTheme", false)
+          .toBool()) {
     // start time
     QDateTime sunrise;
-    sunrise.setSecsSinceEpoch(settings.value("sunrise").toLongLong());
+    sunrise.setSecsSinceEpoch(
+        SettingsManager::instance().settings().value("sunrise").toLongLong());
     // end time
     QDateTime sunset;
-    sunset.setSecsSinceEpoch(settings.value("sunset").toLongLong());
+    sunset.setSecsSinceEpoch(
+        SettingsManager::instance().settings().value("sunset").toLongLong());
     QDateTime currentTime = QDateTime::currentDateTime();
 
     int sunsetSeconds = QTime(0, 0).secsTo(sunset.time());
@@ -185,8 +247,10 @@ void SettingsWidget::themeSwitchTimerTimeout() {
 }
 
 void SettingsWidget::updateAutomaticTheme() {
-  bool automaticThemeSwitching =
-      settings.value("automaticTheme", false).toBool();
+  bool automaticThemeSwitching = SettingsManager::instance()
+                                     .settings()
+                                     .value("automaticTheme", false)
+                                     .toBool();
   if (automaticThemeSwitching && !themeSwitchTimer->isActive()) {
     themeSwitchTimer->start();
   } else if (!automaticThemeSwitching) {
@@ -228,7 +292,10 @@ void SettingsWidget::loadDictionaries(QStringList dictionaries) {
   ui->dictComboBox->blockSignals(false);
 
   // load settings for spellcheck dictionary
-  QString dictionary_name = settings.value("sc_dict", "en-US").toString();
+  QString dictionary_name = SettingsManager::instance()
+                                .settings()
+                                .value("sc_dict", "en-US")
+                                .toString();
   int pos = ui->dictComboBox->findText(dictionary_name);
   if (pos == -1) {
     pos = ui->dictComboBox->findText("en-US");
@@ -241,13 +308,19 @@ void SettingsWidget::loadDictionaries(QStringList dictionaries) {
 
 void SettingsWidget::refresh() {
   ui->themeComboBox->setCurrentText(
-      utils::toCamelCase(settings.value("windowTheme", "light").toString()));
+      Utils::toCamelCase(SettingsManager::instance()
+                             .settings()
+                             .value("windowTheme", "light")
+                             .toString()));
 
-  ui->cookieSize->setText(utils::refreshCacheSize(persistentStoragePath()));
+  ui->cookieSize->setText(Utils::refreshCacheSize(persistentStoragePath()));
 
   // update dict settings at runtime
   //  load settings for spellcheck dictionary
-  QString dictionary_name = settings.value("sc_dict", "en-US").toString();
+  QString dictionary_name = SettingsManager::instance()
+                                .settings()
+                                .value("sc_dict", "en-US")
+                                .toString();
   int pos = ui->dictComboBox->findText(dictionary_name);
   if (pos == -1) {
     pos = ui->dictComboBox->findText("en-US");
@@ -258,8 +331,14 @@ void SettingsWidget::refresh() {
   ui->dictComboBox->setCurrentIndex(pos);
 
   // enable disable spell check
-  ui->enableSpellCheck->setChecked(settings.value("sc_enabled", true).toBool());
-  emit updateFullWidthView(settings.value("fullWidthView", true).toBool());
+  ui->enableSpellCheck->setChecked(SettingsManager::instance()
+                                       .settings()
+                                       .value("sc_enabled", true)
+                                       .toBool());
+  emit updateFullWidthView(SettingsManager::instance()
+                               .settings()
+                               .value("fullWidthView", true)
+                               .toBool());
 }
 
 void SettingsWidget::updateDefaultUAButton(const QString engineUA) {
@@ -301,18 +380,20 @@ void SettingsWidget::on_deletePersistentData_clicked() {
 }
 
 void SettingsWidget::clearAllData() {
-  utils::delete_cache(this->cachePath());
-  utils::delete_cache(this->persistentStoragePath());
+  Utils::delete_cache(this->cachePath());
+  Utils::delete_cache(this->persistentStoragePath());
   refresh();
 }
 
 void SettingsWidget::on_notificationCheckBox_toggled(bool checked) {
-  settings.setValue("disableNotificationPopups", checked);
+  SettingsManager::instance().settings().setValue("disableNotificationPopups",
+                                                  checked);
 }
 
 void SettingsWidget::on_themeComboBox_currentTextChanged(const QString &arg1) {
   applyThemeQuirks();
-  settings.setValue("windowTheme", QString(arg1).toLower());
+  SettingsManager::instance().settings().setValue("windowTheme",
+                                                  QString(arg1).toLower());
   emit updateWindowTheme();
   emit updatePageTheme();
 }
@@ -344,12 +425,12 @@ void SettingsWidget::applyThemeQuirks() {
 }
 
 void SettingsWidget::on_muteAudioCheckBox_toggled(bool checked) {
-  settings.setValue("muteAudio", checked);
+  SettingsManager::instance().settings().setValue("muteAudio", checked);
   emit muteToggled(checked);
 }
 
 void SettingsWidget::on_autoPlayMediaCheckBox_toggled(bool checked) {
-  settings.setValue("autoPlayMedia", checked);
+  SettingsManager::instance().settings().setValue("autoPlayMedia", checked);
   emit autoPlayMediaToggled(checked);
 }
 
@@ -362,10 +443,12 @@ void SettingsWidget::on_userAgentLineEdit_textChanged(const QString &arg1) {
   bool isDefault = QString::compare(arg1.trimmed(), defaultUserAgentStr,
                                     Qt::CaseInsensitive) == 0;
   bool isPrevious =
-      QString::compare(
-          arg1.trimmed(),
-          settings.value("useragent", defaultUserAgentStr).toString(),
-          Qt::CaseInsensitive) == 0;
+      QString::compare(arg1.trimmed(),
+                       SettingsManager::instance()
+                           .settings()
+                           .value("useragent", defaultUserAgentStr)
+                           .toString(),
+                       Qt::CaseInsensitive) == 0;
 
   if (isDefault == false && arg1.trimmed().isEmpty() == false) {
     ui->defaultUserAgentButton->setEnabled(false);
@@ -392,7 +475,8 @@ void SettingsWidget::on_setUserAgent_clicked() {
 
 void SettingsWidget::on_closeButtonActionComboBox_currentIndexChanged(
     int index) {
-  settings.setValue("closeButtonActionCombo", index);
+  SettingsManager::instance().settings().setValue("closeButtonActionCombo",
+                                                  index);
 }
 
 void SettingsWidget::autoAppLockSetChecked(bool checked) {
@@ -403,7 +487,11 @@ void SettingsWidget::autoAppLockSetChecked(bool checked) {
 
 void SettingsWidget::updateAppLockPasswordViewer() {
   this->setCurrentPasswordText(
-      QByteArray::fromBase64(settings.value("asdfg").toString().toUtf8()));
+      QByteArray::fromBase64(SettingsManager::instance()
+                                 .settings()
+                                 .value("asdfg")
+                                 .toString()
+                                 .toUtf8()));
 }
 
 void SettingsWidget::appLockSetChecked(bool checked) {
@@ -420,7 +508,10 @@ void SettingsWidget::appAutoLockingSetChecked(bool checked) {
 
 void SettingsWidget::toggleTheme() {
   // disable automatic theme first
-  if (settings.value("automaticTheme", false).toBool()) {
+  if (SettingsManager::instance()
+          .settings()
+          .value("automaticTheme", false)
+          .toBool()) {
     emit notify(tr(
         "Automatic theme switching was disabled due to manual theme toggle."));
     ui->automaticThemeCheckBox->setChecked(false);
@@ -444,14 +535,15 @@ void SettingsWidget::setCurrentPasswordText(QString str) {
 }
 
 void SettingsWidget::on_applock_checkbox_toggled(bool checked) {
-  if (settings.value("asdfg").isValid()) {
-    settings.setValue("lockscreen", checked);
-  } else if (checked && !settings.value("asdfg").isValid()) {
-    settings.setValue("lockscreen", true);
+  if (SettingsManager::instance().settings().value("asdfg").isValid()) {
+    SettingsManager::instance().settings().setValue("lockscreen", checked);
+  } else if (checked &&
+             !SettingsManager::instance().settings().value("asdfg").isValid()) {
+    SettingsManager::instance().settings().setValue("lockscreen", true);
     if (checked)
       showSetApplockPasswordDialog();
   } else {
-    settings.setValue("lockscreen", false);
+    SettingsManager::instance().settings().setValue("lockscreen", false);
     if (checked)
       showSetApplockPasswordDialog();
   }
@@ -477,12 +569,12 @@ void SettingsWidget::showSetApplockPasswordDialog() {
 }
 
 void SettingsWidget::on_dictComboBox_currentIndexChanged(const QString &arg1) {
-  settings.setValue("sc_dict", arg1);
+  SettingsManager::instance().settings().setValue("sc_dict", arg1);
   emit dictChanged(arg1);
 }
 
 void SettingsWidget::on_enableSpellCheck_toggled(bool checked) {
-  settings.setValue("sc_enabled", checked);
+  SettingsManager::instance().settings().setValue("sc_enabled", checked);
   emit spellCheckChanged(checked);
 }
 
@@ -534,12 +626,13 @@ void SettingsWidget::on_showPermissionsButton_clicked() {
 }
 
 void SettingsWidget::on_notificationTimeOutspinBox_valueChanged(int arg1) {
-  settings.setValue("notificationTimeOut", arg1 * 1000);
+  SettingsManager::instance().settings().setValue("notificationTimeOut",
+                                                  arg1 * 1000);
   emit notificationPopupTimeOutChanged();
 }
 
 void SettingsWidget::on_notificationCombo_currentIndexChanged(int index) {
-  settings.setValue("notificationCombo", index);
+  SettingsManager::instance().settings().setValue("notificationCombo", index);
 }
 
 void SettingsWidget::on_tryNotification_clicked() {
@@ -555,8 +648,10 @@ void SettingsWidget::on_automaticThemeCheckBox_toggled(bool checked) {
     automaticTheme->setAttribute(Qt::WA_DeleteOnClose, true);
     connect(automaticTheme, &AutomaticTheme::destroyed,
             ui->automaticThemeCheckBox, [=]() {
-              bool automaticThemeSwitching =
-                  settings.value("automaticTheme", false).toBool();
+              bool automaticThemeSwitching = SettingsManager::instance()
+                                                 .settings()
+                                                 .value("automaticTheme", false)
+                                                 .toBool();
               ui->automaticThemeCheckBox->setChecked(automaticThemeSwitching);
               if (automaticThemeSwitching)
                 themeSwitchTimerTimeout();
@@ -564,28 +659,30 @@ void SettingsWidget::on_automaticThemeCheckBox_toggled(bool checked) {
             });
     automaticTheme->show();
   } else {
-    settings.setValue("automaticTheme", false);
+    SettingsManager::instance().settings().setValue("automaticTheme", false);
     updateAutomaticTheme();
   }
 }
 
 void SettingsWidget::on_useNativeFileDialog_toggled(bool checked) {
-  settings.setValue("useNativeFileDialog", checked);
+  SettingsManager::instance().settings().setValue("useNativeFileDialog",
+                                                  checked);
 }
 
 void SettingsWidget::on_startMinimized_toggled(bool checked) {
-  settings.setValue("startMinimized", checked);
+  SettingsManager::instance().settings().setValue("startMinimized", checked);
 }
 
 void SettingsWidget::on_appAutoLockcheckBox_toggled(bool checked) {
-  if (settings.value("asdfg").isValid()) {
-    settings.setValue("appAutoLocking", checked);
+  if (SettingsManager::instance().settings().value("asdfg").isValid()) {
+    SettingsManager::instance().settings().setValue("appAutoLocking", checked);
   } else {
     QMessageBox::information(this, "App Lock Setup",
                              "Please setup the App lock password first.",
                              QMessageBox::Ok);
-    if (settings.value("asdfg").isValid() == false) {
-      settings.setValue("appAutoLocking", false);
+    if (SettingsManager::instance().settings().value("asdfg").isValid() ==
+        false) {
+      SettingsManager::instance().settings().setValue("appAutoLocking", false);
       autoAppLockSetChecked(false);
     }
   }
@@ -593,7 +690,7 @@ void SettingsWidget::on_appAutoLockcheckBox_toggled(bool checked) {
 }
 
 void SettingsWidget::on_autoLockDurationSpinbox_valueChanged(int arg1) {
-  settings.setValue("autoLockDuration", arg1);
+  SettingsManager::instance().settings().setValue("autoLockDuration", arg1);
   emit appAutoLockChanged();
 }
 
@@ -603,64 +700,78 @@ void SettingsWidget::on_resetAppAutoLockPushButton_clicked() {
 }
 
 void SettingsWidget::on_minimizeOnTrayIconClick_toggled(bool checked) {
-  settings.setValue("minimizeOnTrayIconClick", checked);
+  SettingsManager::instance().settings().setValue("minimizeOnTrayIconClick",
+                                                  checked);
 }
 
 void SettingsWidget::on_styleComboBox_currentTextChanged(const QString &arg1) {
   applyThemeQuirks();
-  settings.setValue("widgetStyle", arg1);
+  SettingsManager::instance().settings().setValue("widgetStyle", arg1);
   emit updateWindowTheme();
   emit updatePageTheme();
 }
 
 void SettingsWidget::on_zoomPlus_clicked() {
-  double currentFactor = settings.value("zoomFactor", 1.0).toDouble();
+  double currentFactor = SettingsManager::instance()
+                             .settings()
+                             .value("zoomFactor", 1.0)
+                             .toDouble();
   double newFactor = currentFactor + 0.25;
   ui->zoomFactorSpinBox->setValue(newFactor);
-  settings.setValue("zoomFactor", ui->zoomFactorSpinBox->value());
+  SettingsManager::instance().settings().setValue(
+      "zoomFactor", ui->zoomFactorSpinBox->value());
   emit zoomChanged();
 }
 
 void SettingsWidget::on_zoomMinus_clicked() {
-  double currentFactor = settings.value("zoomFactor", 1.0).toDouble();
+  double currentFactor = SettingsManager::instance()
+                             .settings()
+                             .value("zoomFactor", 1.0)
+                             .toDouble();
   double newFactor = currentFactor - 0.25;
   ui->zoomFactorSpinBox->setValue(newFactor);
-  settings.setValue("zoomFactor", ui->zoomFactorSpinBox->value());
+  SettingsManager::instance().settings().setValue(
+      "zoomFactor", ui->zoomFactorSpinBox->value());
   emit zoomChanged();
 }
 
 void SettingsWidget::on_zoomReset_clicked() {
   ui->zoomFactorSpinBox->setValue(1.0);
-  settings.setValue("zoomFactor", ui->zoomFactorSpinBox->value());
+  SettingsManager::instance().settings().setValue(
+      "zoomFactor", ui->zoomFactorSpinBox->value());
   emit zoomChanged();
 }
 
 void SettingsWidget::on_zoomResetMaximized_clicked() {
   ui->zoomFactorSpinBoxMaximized->setValue(defaultZoomFactorMaximized);
-  settings.setValue("zoomFactorMaximized",
-                    ui->zoomFactorSpinBoxMaximized->value());
+  SettingsManager::instance().settings().setValue(
+      "zoomFactorMaximized", ui->zoomFactorSpinBoxMaximized->value());
   emit zoomMaximizedChanged();
 }
 
 void SettingsWidget::on_zoomPlusMaximized_clicked() {
   double currentFactor =
-      settings.value("zoomFactorMaximized", defaultZoomFactorMaximized)
+      SettingsManager::instance()
+          .settings()
+          .value("zoomFactorMaximized", defaultZoomFactorMaximized)
           .toDouble();
   double newFactor = currentFactor + 0.25;
   ui->zoomFactorSpinBoxMaximized->setValue(newFactor);
-  settings.setValue("zoomFactorMaximized",
-                    ui->zoomFactorSpinBoxMaximized->value());
+  SettingsManager::instance().settings().setValue(
+      "zoomFactorMaximized", ui->zoomFactorSpinBoxMaximized->value());
   emit zoomMaximizedChanged();
 }
 
 void SettingsWidget::on_zoomMinusMaximized_clicked() {
   double currentFactor =
-      settings.value("zoomFactorMaximized", defaultZoomFactorMaximized)
+      SettingsManager::instance()
+          .settings()
+          .value("zoomFactorMaximized", defaultZoomFactorMaximized)
           .toDouble();
   double newFactor = currentFactor - 0.25;
   ui->zoomFactorSpinBoxMaximized->setValue(newFactor);
-  settings.setValue("zoomFactorMaximized",
-                    ui->zoomFactorSpinBoxMaximized->value());
+  SettingsManager::instance().settings().setValue(
+      "zoomFactorMaximized", ui->zoomFactorSpinBoxMaximized->value());
   emit zoomMaximizedChanged();
 }
 
@@ -670,12 +781,15 @@ void SettingsWidget::on_changeDefaultDownloadLocationPb_clicked() {
   dialog.setOption(QFileDialog::ShowDirsOnly);
 
   QString path;
-  bool usenativeFileDialog =
-      settings.value("useNativeFileDialog", false).toBool();
+  bool usenativeFileDialog = SettingsManager::instance()
+                                 .settings()
+                                 .value("useNativeFileDialog", false)
+                                 .toBool();
   if (usenativeFileDialog == false) {
     path = QFileDialog::getExistingDirectory(
         this, tr("Select download directory"),
-        settings
+        SettingsManager::instance()
+            .settings()
             .value("defaultDownloadLocation",
                    QStandardPaths::writableLocation(
                        QStandardPaths::DownloadLocation) +
@@ -685,7 +799,8 @@ void SettingsWidget::on_changeDefaultDownloadLocationPb_clicked() {
   } else {
     path = QFileDialog::getSaveFileName(
         this, tr("Select download directory"),
-        settings
+        SettingsManager::instance()
+            .settings()
             .value("defaultDownloadLocation",
                    QStandardPaths::writableLocation(
                        QStandardPaths::DownloadLocation) +
@@ -695,7 +810,8 @@ void SettingsWidget::on_changeDefaultDownloadLocationPb_clicked() {
 
   if (!path.isNull() && !path.isEmpty()) {
     ui->defaultDownloadLocation->setText(path);
-    settings.setValue("defaultDownloadLocation", path);
+    SettingsManager::instance().settings().setValue("defaultDownloadLocation",
+                                                    path);
   }
 }
 
@@ -720,7 +836,7 @@ void SettingsWidget::on_viewPassword_clicked() {
 }
 
 void SettingsWidget::on_chnageCurrentPasswordPushButton_clicked() {
-  if (settings.value("asdfg").isValid()) {
+  if (SettingsManager::instance().settings().value("asdfg").isValid()) {
     QMessageBox msgBox;
     msgBox.setText("You are about to change your current app lock password!"
                    "\n\nThis will LogOut your current session."
@@ -741,20 +857,19 @@ void SettingsWidget::on_chnageCurrentPasswordPushButton_clicked() {
     msgBox.exec();
 
   } else {
-    settings.setValue("lockscreen", true);
+    SettingsManager::instance().settings().setValue("lockscreen", true);
     showSetApplockPasswordDialog();
   }
 }
 
 void SettingsWidget::on_fullWidthViewCheckbox_toggled(bool checked) {
-  settings.setValue("fullWidthView", checked);
+  SettingsManager::instance().settings().setValue("fullWidthView", checked);
   emit updateFullWidthView(checked);
 }
 
-void SettingsWidget::keyPressEvent(QKeyEvent *e)
-{
-   if (e->key() == Qt::Key_Escape)
-      this->close();
+void SettingsWidget::keyPressEvent(QKeyEvent *e) {
+  if (e->key() == Qt::Key_Escape)
+    this->close();
 
-   QWidget::keyPressEvent(e);
+  QWidget::keyPressEvent(e);
 }
diff --git a/src/settingswidget.h b/src/settingswidget.h
index d533343..a569d6f 100644
--- a/src/settingswidget.h
+++ b/src/settingswidget.h
@@ -1,12 +1,12 @@
 #ifndef SETTINGSWIDGET_H
 #define SETTINGSWIDGET_H
 
+#include <QWidget>
+
 #include "permissiondialog.h"
+#include "settingsmanager.h"
 #include "utils.h"
 
-#include <QSettings>
-#include <QWidget>
-
 namespace Ui {
 class SettingsWidget;
 }
@@ -102,7 +102,6 @@ private slots:
 private:
   Ui::SettingsWidget *ui;
   QString engineCachePath, enginePersistentStoragePath;
-  QSettings settings;
   QTimer *themeSwitchTimer;
 };
 
diff --git a/src/theme.cpp b/src/theme.cpp
new file mode 100644
index 0000000..742e59d
--- /dev/null
+++ b/src/theme.cpp
@@ -0,0 +1,69 @@
+#include "theme.h"
+
+QPalette Theme::initLightPalette() {
+  QPalette lightPalette;
+  lightPalette.setColor(QPalette::Window, QColor(240, 240, 240));
+  lightPalette.setColor(QPalette::WindowText, QColor(0, 0, 0));
+  lightPalette.setColor(QPalette::Button, QColor(240, 240, 240));
+  lightPalette.setColor(QPalette::Light, QColor(180, 180, 180));
+  lightPalette.setColor(QPalette::Midlight, QColor(200, 200, 200));
+  lightPalette.setColor(QPalette::Dark, QColor(225, 225, 225));
+  lightPalette.setColor(QPalette::Text, QColor(0, 0, 0));
+  lightPalette.setColor(QPalette::BrightText, QColor(0, 0, 0));
+  lightPalette.setColor(QPalette::ButtonText, QColor(0, 0, 0));
+  lightPalette.setColor(QPalette::Base, QColor(237, 237, 237));
+  lightPalette.setColor(QPalette::Shadow, QColor(20, 20, 20));
+  lightPalette.setColor(QPalette::Highlight, QColor(76, 163, 224));
+  lightPalette.setColor(QPalette::HighlightedText, QColor(0, 0, 0));
+  lightPalette.setColor(QPalette::Link, QColor(0, 162, 232));
+  lightPalette.setColor(QPalette::AlternateBase, QColor(225, 225, 225));
+  lightPalette.setColor(QPalette::ToolTipBase, QColor(240, 240, 240));
+  lightPalette.setColor(QPalette::ToolTipText, QColor(0, 0, 0));
+  lightPalette.setColor(QPalette::LinkVisited, QColor(222, 222, 222));
+  lightPalette.setColor(QPalette::Disabled, QPalette::WindowText,
+                        QColor(115, 115, 115));
+  lightPalette.setColor(QPalette::Disabled, QPalette::Text,
+                        QColor(115, 115, 115));
+  lightPalette.setColor(QPalette::Disabled, QPalette::ButtonText,
+                        QColor(115, 115, 115));
+  lightPalette.setColor(QPalette::Disabled, QPalette::Highlight,
+                        QColor(190, 190, 190));
+  lightPalette.setColor(QPalette::Disabled, QPalette::HighlightedText,
+                        QColor(115, 115, 115));
+
+  return lightPalette;
+}
+
+QPalette Theme::initDarkPalette() {
+  QPalette darkPalette;
+  darkPalette.setColor(QPalette::Window, QColor(17, 27, 33));
+  darkPalette.setColor(QPalette::Text, Qt::white);
+  darkPalette.setColor(QPalette::WindowText, Qt::white);
+  darkPalette.setColor(QPalette::Base, QColor(32, 44, 51));
+  darkPalette.setColor(QPalette::AlternateBase, QColor(95, 108, 115));
+  darkPalette.setColor(QPalette::ToolTipBase, QColor(66, 66, 66));
+  darkPalette.setColor(QPalette::ToolTipText, QColor(192, 192, 192));
+  darkPalette.setColor(QPalette::Dark, QColor(35, 35, 35));
+  darkPalette.setColor(QPalette::Shadow, QColor(20, 20, 20));
+  darkPalette.setColor(QPalette::Button, QColor(17, 27, 33));
+  darkPalette.setColor(QPalette::ButtonText, Qt::white);
+  darkPalette.setColor(QPalette::BrightText, Qt::red);
+  darkPalette.setColor(QPalette::Link, QColor(42, 130, 218));
+  darkPalette.setColor(QPalette::Highlight, QColor(38, 140, 196));
+  darkPalette.setColor(QPalette::HighlightedText, Qt::white);
+  darkPalette.setColor(QPalette::Disabled, QPalette::HighlightedText,
+                       QColor(127, 127, 127));
+  darkPalette.setColor(QPalette::Disabled, QPalette::Window,
+                       QColor(65, 65, 67));
+  darkPalette.setColor(QPalette::Disabled, QPalette::Highlight,
+                       QColor(80, 80, 80));
+  darkPalette.setColor(QPalette::Disabled, QPalette::ButtonText,
+                       QColor(127, 127, 127));
+  darkPalette.setColor(QPalette::Disabled, QPalette::Text,
+                       QColor(127, 127, 127));
+  return darkPalette;
+}
+
+QPalette &Theme::getLightPalette() { return lightPalette(); }
+
+QPalette &Theme::getDarkPalette() { return darkPalette(); }
diff --git a/src/theme.h b/src/theme.h
new file mode 100644
index 0000000..71b7306
--- /dev/null
+++ b/src/theme.h
@@ -0,0 +1,27 @@
+#ifndef THEME_H
+#define THEME_H
+
+#include <QColor>
+#include <QDebug>
+#include <QPalette>
+
+class Theme {
+public:
+  static QPalette &getLightPalette();
+  static QPalette &getDarkPalette();
+
+private:
+  static QPalette &lightPalette() {
+    static QPalette palette = initLightPalette();
+    return palette;
+  }
+  static QPalette &darkPalette() {
+    static QPalette palette = initDarkPalette();
+    return palette;
+  }
+
+  static QPalette initLightPalette();
+  static QPalette initDarkPalette();
+};
+
+#endif // THEME_H
diff --git a/src/utils.cpp b/src/utils.cpp
index c00b25d..46365e7 100644
--- a/src/utils.cpp
+++ b/src/utils.cpp
@@ -2,12 +2,12 @@
 #include "def.h"
 #include <time.h>
 
-utils::utils(QObject *parent) : QObject(parent) { setParent(parent); }
+Utils::Utils(QObject *parent) : QObject(parent) { setParent(parent); }
 
-utils::~utils() { this->deleteLater(); }
+Utils::~Utils() { this->deleteLater(); }
 
 // calculate dir size
-quint64 utils::dir_size(const QString &directory) {
+quint64 Utils::dir_size(const QString &directory) {
   quint64 sizex = 0;
   QFileInfo str_info(directory);
   if (str_info.isDir()) {
@@ -28,7 +28,7 @@ quint64 utils::dir_size(const QString &directory) {
 }
 
 // get the size of cache folder in human readble format
-QString utils::refreshCacheSize(const QString cache_dir) {
+QString Utils::refreshCacheSize(const QString cache_dir) {
   qint64 cache_size = dir_size(cache_dir);
   QString cache_unit;
   if (cache_size > 1024 * 1024 * 1024) {
@@ -47,25 +47,25 @@ QString utils::refreshCacheSize(const QString cache_dir) {
   return QString::number(cache_size) + cache_unit;
 }
 
-bool utils::delete_cache(const QString cache_dir) {
+bool Utils::delete_cache(const QString cache_dir) {
   bool deleted = QDir(cache_dir).removeRecursively();
   QDir(cache_dir).mkpath(cache_dir);
   return deleted;
 }
 
 // returns string with first letter capitalized
-QString utils::toCamelCase(const QString &s) {
+QString Utils::toCamelCase(const QString &s) {
   QStringList parts = s.split(' ', Qt::SkipEmptyParts);
   for (int i = 0; i < parts.size(); ++i)
     parts[i].replace(0, 1, parts[i][0].toUpper());
   return parts.join(" ");
 }
 
-QString utils::generateRandomId(int length) {
+QString Utils::generateRandomId(int length) {
   return genRand(length, false, true, false);
 }
 
-QString utils::genRand(int length, bool useUpper, bool useLower,
+QString Utils::genRand(int length, bool useUpper, bool useLower,
                        bool useDigits) {
   QString possibleCharacters;
   if (useUpper) {
@@ -93,7 +93,7 @@ QString utils::genRand(int length, bool useUpper, bool useLower,
   return QString::fromLatin1(randomBytes);
 }
 
-QString utils::convertSectoDay(qint64 secs) {
+QString Utils::convertSectoDay(qint64 secs) {
   int day = secs / (24 * 3600);
 
   secs = secs % (24 * 3600);
@@ -111,9 +111,28 @@ QString utils::convertSectoDay(qint64 secs) {
   return days;
 }
 
-// static on demand path maker
+/**
+ * @brief Returns the full path for a given file or directory name within a
+ * specified location.
+ *
+ * The method constructs the full path by concatenating the specified `pathname`
+ * with the provided `standardLocation`. If `standardLocation` is not provided,
+ * the default value is obtained from
+ * `QStandardPaths::writableLocation(QStandardPaths::DataLocation)`.
+ *
+ * @param pathname The name of the file or directory within the specified
+ * location.
+ * @param standardLocation (optional) The base directory to prepend to
+ * `pathname`. Default value:
+ * QStandardPaths::writableLocation(QStandardPaths::DataLocation).
+ *
+ * @return The full path, including the `pathname` and the `standardLocation`,
+ * separated by the appropriate directory separator. If the specified location
+ * does not exist, the method creates it using QDir::mkpath. The returned path
+ * ends with a directory separator.
+ */
 QString
-utils::returnPath(QString pathname,
+Utils::returnPath(QString pathname,
                   QString standardLocation = QStandardPaths::writableLocation(
                       QStandardPaths::DataLocation)) {
   QChar sepe = QDir::separator();
@@ -122,10 +141,24 @@ utils::returnPath(QString pathname,
   return standardLocation + sepe + pathname + sepe;
 }
 
-QString utils::EncodeXML(const QString &encodeMe) {
-
+/**
+ * @brief Encodes XML special characters in a given string and returns the
+ * encoded version.
+ *
+ * The method iterates over each character in the input `encodeMe` string and
+ * replaces XML special characters
+ * ('&', '\'', '"', '<', and '>') with their corresponding XML entities
+ * ('&amp;', '&apos;', '&quot;', '&lt;', and '&gt;'). The encoded string is then
+ * returned.
+ *
+ * @param encodeMe The string to be encoded.
+ * @return The encoded version of the input string, where XML special characters
+ * are replaced with their corresponding entities.
+ */
+QString Utils::encodeXML(const QString &encodeMe) {
   QString temp;
   int length = encodeMe.size();
+
   for (int index = 0; index < length; index++) {
     QChar character(encodeMe.at(index));
 
@@ -159,8 +192,20 @@ QString utils::EncodeXML(const QString &encodeMe) {
   return temp;
 }
 
-QString utils::DecodeXML(const QString &decodeMe) {
-
+/**
+ * @brief Decodes XML entities in a given string and returns the decoded
+ * version.
+ *
+ * The method creates a copy of the input `decodeMe` string and replaces XML
+ * entities
+ * ('&amp;', '&apos;', '&quot;', '&lt;', and '&gt;') with their corresponding
+ * characters. The decoded string is then returned.
+ *
+ * @param decodeMe The string to be decoded.
+ * @return The decoded version of the input string, where XML entities are
+ * replaced with their corresponding characters.
+ */
+QString Utils::decodeXML(const QString &decodeMe) {
   QString temp(decodeMe);
 
   temp.replace("&amp;", "&");
@@ -172,45 +217,96 @@ QString utils::DecodeXML(const QString &decodeMe) {
   return temp;
 }
 
-QString utils::htmlToPlainText(const QString &str) {
-  QString out;
-  QTextDocument text;
-  text.setHtml(str);
-  out = text.toPlainText();
-  text.deleteLater();
-  return out.replace("\\\"", "'")
-      .replace("&amp;", "&")
-      .replace("&gt;", ">")
-      .replace("&lt;", "<")
-      .replace("&#39;", "'");
+/**
+ * @brief Retrieves the installation type based on the environment variables and
+ * heuristics.
+ *
+ * The method retrieves the value of the "INSTALL_TYPE" environment variable
+ * using QProcessEnvironment. If the "INSTALL_TYPE" variable is empty, the
+ * method performs heuristics to determine the installation type. It checks if
+ * the "SNAP" environment variable is set, in which case the installation type
+ * is considered as "snap". If the "SNAP" variable is not set, it checks if the
+ * "FLATPAK_ID" environment variable is not empty, in which case the
+ * installation type is considered as "flatpak".
+ *
+ * @return The installation type as a QString. It can be "snap", "flatpak", or
+ * an empty string if the installation type could not be determined.
+ */
+QString Utils::getInstallType() {
+  QProcessEnvironment env = QProcessEnvironment::systemEnvironment();
+
+  // Retrieve the value of "INSTALL_TYPE" environment variable
+  QString installType = env.value("INSTALL_TYPE");
+
+  // Try guessing if it is empty
+  if (installType.isEmpty()) {
+    if (env.contains("SNAP")) {
+      installType = "snap";
+    } else if (env.value("FLATPAK_ID").trimmed().isEmpty() == false) {
+      installType = "flatpak";
+    }
+  }
+
+  return installType.trimmed();
 }
 
-QString utils::appDebugInfo() {
+/**
+ * @brief Retrieves debug information about the application.
+ *
+ * The method generates a formatted string containing various debug information
+ * about the application. It includes information such as the application name,
+ * version, source branch, commit hash, build datetime, Qt runtime version, Qt
+ * compiled version, system information, and installation mode.
+ *
+ * @return A QString containing the debug information about the application.
+ */
+QString Utils::appDebugInfo() {
+  QString installType = Utils::getInstallType();
+  installType =
+      "<li><b>" + QObject::tr("Install mode") + ":</b>        " +
+      QString(installType.trimmed().isEmpty() ? "Unknown" : installType) +
+      "</li>";
+
+  QString applicationName = QApplication::applicationName();
+  QString version = QString(VERSIONSTR);
+  QString sourceBranch = QString(GIT_BRANCH);
+  QString commitHash = QString(GIT_HASH);
+  QString buildDatetime = QString::fromLatin1(BUILD_TIMESTAMP);
+  QString qtRuntimeVersion = QString(qVersion());
+  QString qtCompiledVersion = QString(QT_VERSION_STR);
+  QString systemInfo = QSysInfo::prettyProductName();
+  QString architecture = QSysInfo::currentCpuArchitecture();
+  QString installMode = Utils::getInstallType();
 
   QStringList debugInfo;
-  debugInfo << "<h3>" + QApplication::applicationName() + "</h3>"
+  debugInfo << "<h3>" + applicationName + "</h3>"
             << "<ul>"
             << "<li><b>" + QObject::tr("Version") + ":</b>             " +
-                   QString(VERSIONSTR) + "</li>"
+                   version + "</li>"
             << "<li><b>" + QObject::tr("Source Branch") + ":</b>             " +
-                   QString(GIT_BRANCH) + "</li>"
+                   sourceBranch + "</li>"
             << "<li><b>" + QObject::tr("Commit Hash") + ":</b>             " +
-                   QString(GIT_HASH) + "</li>"
+                   commitHash + "</li>"
             << "<li><b>" + QObject::tr("Build Datetime") + ":</b>          " +
-                   QString::fromLatin1(BUILD_TIMESTAMP) + "</li>"
+                   buildDatetime + "</li>"
             << "<li><b>" + QObject::tr("Qt Runtime Version") + ":</b>   " +
-                   QString(qVersion()) + "</li>"
+                   qtRuntimeVersion + "</li>"
             << "<li><b>" + QObject::tr("Qt Compiled Version") + ":</b> " +
-                   QString(QT_VERSION_STR) + "</li>"
+                   qtCompiledVersion + "</li>"
             << "<li><b>" + QObject::tr("System") + ":</b>              " +
-                   QSysInfo::prettyProductName() + "</li>"
+                   systemInfo + "</li>"
             << "<li><b>" + QObject::tr("Architecture") + ":</b>        " +
-                   QSysInfo::currentCpuArchitecture() + "</li>";
-  debugInfo << "</ul>";
+                   architecture + "</li>"
+            << "<li><b>" + QObject::tr("Install mode") + ":</b>        " +
+                   QString(installMode.trimmed().isEmpty() ? "Unknown"
+                                                           : installMode) +
+                   "</li>"
+            << "</ul>";
+
   return debugInfo.join("\n");
 }
 
-void utils::DisplayExceptionErrorDialog(const QString &error_info) {
+void Utils::DisplayExceptionErrorDialog(const QString &error_info) {
   QMessageBox message_box(QApplication::activeWindow());
   message_box.setAttribute(Qt::WA_DeleteOnClose, true);
   message_box.setWindowFlags(Qt::Window | Qt::WindowStaysOnTopHint);
@@ -235,19 +331,31 @@ void utils::DisplayExceptionErrorDialog(const QString &error_info) {
                 << "\nQt Runtime Version: " + QString(qVersion())
                 << "\nQt Compiled Version: " + QString(QT_VERSION_STR)
                 << "\nSystem: " + QSysInfo::prettyProductName()
-                << "\nArchitecture: " + QSysInfo::currentCpuArchitecture();
+                << "\nArchitecture: " + QSysInfo::currentCpuArchitecture()
+                << "\nInstall type: " + Utils::getInstallType();
   message_box.setDetailedText(detailed_text.join("\n"));
   message_box.exec();
 }
 
-// Returns the same number, but rounded to one decimal place
-float utils::RoundToOneDecimal(float number) {
+/**
+ * Returns the same number, but rounded to one decimal place
+ *
+ * @brief Utils::RoundToOneDecimal
+ * @param number
+ * @return
+ */
+float Utils::RoundToOneDecimal(float number) {
   return QString::number(number, 'f', 1).toFloat();
 }
 
-// Returns a value for the environment variable name passed;
-// if the env var isn't set, it returns an empty string
-QString utils::GetEnvironmentVar(const QString &variable_name) {
+/**
+ * Returns a value for the environment variable name passed;
+ * if the env var isn't set, it returns an empty string
+ * @brief Utils::GetEnvironmentVar
+ * @param variable_name
+ * @return
+ */
+QString Utils::GetEnvironmentVar(const QString &variable_name) {
 #if QT_VERSION >= QT_VERSION_CHECK(5, 10, 0)
   // The only time this might fall down is on Linux when an
   // environment variable holds bytedata. Don't use this
@@ -261,14 +369,24 @@ QString utils::GetEnvironmentVar(const QString &variable_name) {
 #endif
 }
 
-void utils::desktopOpenUrl(const QString &str) {
+/**
+ * @brief Opens the specified URL in the default desktop application.
+ *
+ * The method attempts to open the URL using the `xdg-open` command-line tool.
+ * If the `xdg-open` process fails to start within 1 second, it falls back to
+ * using `QDesktopServices` to open the URL. If both methods fail, a warning
+ * message is printed to the console.
+ *
+ * @param str The URL to be opened.
+ */
+void Utils::desktopOpenUrl(const QString &str) {
   QProcess *xdg_open = new QProcess(0);
   xdg_open->start("xdg-open", QStringList() << str);
   if (xdg_open->waitForStarted(1000) == false) {
-    // try using QdesktopServices
+    // Try using QDesktopServices
     bool opened = QDesktopServices::openUrl(QUrl(str));
     if (opened == false) {
-      qWarning() << "failed to open url" << str;
+      qWarning() << "Failed to open URL:" << str;
     }
   }
   connect(xdg_open,
@@ -282,7 +400,7 @@ void utils::desktopOpenUrl(const QString &str) {
           });
 }
 
-bool utils::isPhoneNumber(const QString &phoneNumber) {
+bool Utils::isPhoneNumber(const QString &phoneNumber) {
   const QString phone = "^\\+(((\\d{2}))\\s?)?((\\d{2})|(\\((\\d{2})\\))\\s?)?("
                         "\\d{3,15})(\\-(\\d{3,15}))?$";
   static QRegularExpression reg(phone);
diff --git a/src/utils.h b/src/utils.h
index c972ba4..76e8043 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -17,22 +17,21 @@
 #include <QTextDocument>
 #include <QUuid>
 
-class utils : public QObject {
+class Utils : public QObject {
   Q_OBJECT
 
 public:
-  utils(QObject *parent = 0);
-  virtual ~utils();
-public slots:
+  Utils(QObject *parent = 0);
+  virtual ~Utils();
+  static QString getInstallType();
   static QString refreshCacheSize(const QString cache_dir);
   static bool delete_cache(const QString cache_dir);
   static QString toCamelCase(const QString &s);
   static QString generateRandomId(int length);
   static QString convertSectoDay(qint64 secs);
   static QString returnPath(QString pathname, QString standardLocation);
-  static QString EncodeXML(const QString &encodeMe);
-  static QString DecodeXML(const QString &decodeMe);
-  static QString htmlToPlainText(const QString &str);
+  static QString encodeXML(const QString &encodeMe);
+  static QString decodeXML(const QString &decodeMe);
   static QString GetEnvironmentVar(const QString &variable_name);
   static float RoundToOneDecimal(float number);
   static void DisplayExceptionErrorDialog(const QString &error_info);
diff --git a/src/webenginepage.cpp b/src/webenginepage.cpp
index c7b7086..7ff4d9c 100644
--- a/src/webenginepage.cpp
+++ b/src/webenginepage.cpp
@@ -1,9 +1,5 @@
 #include "webenginepage.h"
 
-#include <QIcon>
-#include <QStyle>
-#include <QWebEngineSettings>
-
 WebEnginePage::WebEnginePage(QWebEngineProfile *profile, QObject *parent)
     : QWebEnginePage(profile, parent) {
 
@@ -75,8 +71,11 @@ inline QString questionForFeature(QWebEnginePage::Feature feature) {
 void WebEnginePage::handleFeaturePermissionRequested(const QUrl &securityOrigin,
                                                      Feature feature) {
   bool autoPlay = true;
-  if (settings.value("autoPlayMedia").isValid())
-    autoPlay = settings.value("autoPlayMedia", false).toBool();
+  if (SettingsManager::instance().settings().value("autoPlayMedia").isValid())
+    autoPlay = SettingsManager::instance()
+                   .settings()
+                   .value("autoPlayMedia", false)
+                   .toBool();
   if (autoPlay && (feature == QWebEnginePage::MediaVideoCapture ||
                    feature == QWebEnginePage::MediaAudioVideoCapture)) {
     QWebEngineProfile *defProfile = QWebEngineProfile::defaultProfile();
@@ -92,8 +91,11 @@ void WebEnginePage::handleFeaturePermissionRequested(const QUrl &securityOrigin,
   QString question = questionForFeature(feature).arg(securityOrigin.host());
 
   QString featureStr = QVariant::fromValue(feature).toString();
-  settings.beginGroup("permissions");
-  if (settings.value(featureStr, false).toBool()) {
+  SettingsManager::instance().settings().beginGroup("permissions");
+  if (SettingsManager::instance()
+          .settings()
+          .value(featureStr, false)
+          .toBool()) {
     setFeaturePermission(
         securityOrigin, feature,
         QWebEnginePage::PermissionPolicy::PermissionGrantedByUser);
@@ -104,29 +106,35 @@ void WebEnginePage::handleFeaturePermissionRequested(const QUrl &securityOrigin,
       setFeaturePermission(
           securityOrigin, feature,
           QWebEnginePage::PermissionPolicy::PermissionGrantedByUser);
-      settings.setValue(featureStr, true);
+      SettingsManager::instance().settings().setValue(featureStr, true);
     } else {
       setFeaturePermission(
           securityOrigin, feature,
           QWebEnginePage::PermissionPolicy::PermissionDeniedByUser);
-      settings.setValue(featureStr, false);
+      SettingsManager::instance().settings().setValue(featureStr, false);
     }
   }
-  settings.endGroup();
+  SettingsManager::instance().settings().endGroup();
 }
 
 void WebEnginePage::handleLoadFinished(bool ok) {
 
   // turn on Notification settings by default
-  if (settings.value("permissions/Notifications").isValid() == false) {
-    settings.beginGroup("permissions");
-    settings.setValue("Notifications", true);
+  if (SettingsManager::instance()
+          .settings()
+          .value("permissions/Notifications")
+          .isValid() == false) {
+    SettingsManager::instance().settings().beginGroup("permissions");
+    SettingsManager::instance().settings().setValue("Notifications", true);
     setFeaturePermission(
         QUrl("https://web.whatsapp.com/"),
         QWebEnginePage::Feature::Notifications,
         QWebEnginePage::PermissionPolicy::PermissionGrantedByUser);
-    settings.endGroup();
-  } else if (settings.value("permissions/Notifications", true).toBool()) {
+    SettingsManager::instance().settings().endGroup();
+  } else if (SettingsManager::instance()
+                 .settings()
+                 .value("permissions/Notifications", true)
+                 .toBool()) {
     setFeaturePermission(
         QUrl("https://web.whatsapp.com/"),
         QWebEnginePage::Feature::Notifications,
@@ -159,8 +167,10 @@ QStringList WebEnginePage::chooseFiles(QWebEnginePage::FileSelectionMode mode,
   }
 
   QFileDialog *dialog = new QFileDialog();
-  bool usenativeFileDialog =
-      settings.value("useNativeFileDialog", false).toBool();
+  bool usenativeFileDialog = SettingsManager::instance()
+                                 .settings()
+                                 .value("useNativeFileDialog", false)
+                                 .toBool();
 
   if (usenativeFileDialog == false) {
     dialog->setOption(QFileDialog::DontUseNativeDialog, true);
@@ -387,7 +397,10 @@ void WebEnginePage::injectMutationObserver() {
 }
 
 void WebEnginePage::injectFullWidthJavaScript() {
-  if (!settings.value("fullWidthView", true).toBool())
+  if (!SettingsManager::instance()
+           .settings()
+           .value("fullWidthView", true)
+           .toBool())
     return;
   QString js =
       R"(function updateFullWidthView(element) {
diff --git a/src/webenginepage.h b/src/webenginepage.h
index d039288..8f05e44 100644
--- a/src/webenginepage.h
+++ b/src/webenginepage.h
@@ -1,22 +1,22 @@
 #ifndef WEBENGINEPAGE_H
 #define WEBENGINEPAGE_H
 
-#include <QFileDialog>
-#include <QWebEngineFullScreenRequest>
-#include <QWebEngineNotification>
-#include <QWebEngineProfile>
-
 #include <QAuthenticator>
 #include <QDesktopServices>
+#include <QFileDialog>
+#include <QIcon>
 #include <QImageReader>
 #include <QMessageBox>
+#include <QStyle>
 #include <QWebEngineCertificateError>
-#include <QWebEnginePage>
-
 #include <QWebEngineFullScreenRequest>
+#include <QWebEngineNotification>
+#include <QWebEnginePage>
+#include <QWebEngineProfile>
 #include <QWebEngineRegisterProtocolHandlerRequest>
+#include <QWebEngineSettings>
 
-#include <QSettings>
+#include "settingsmanager.h"
 
 #include "ui_certificateerrordialog.h"
 #include "ui_passworddialog.h"
@@ -26,9 +26,6 @@ class WebEnginePage : public QWebEnginePage {
 public:
   WebEnginePage(QWebEngineProfile *profile, QObject *parent = nullptr);
 
-private:
-  QSettings settings;
-
 protected:
   bool acceptNavigationRequest(const QUrl &url,
                                QWebEnginePage::NavigationType type,
@@ -36,7 +33,7 @@ protected:
   QWebEnginePage *createWindow(QWebEnginePage::WebWindowType type) override;
   bool certificateError(const QWebEngineCertificateError &error) override;
   QStringList chooseFiles(FileSelectionMode mode, const QStringList &oldFiles,
-                          const QStringList &acceptedMimeTypes);
+                          const QStringList &acceptedMimeTypes) override;
 
 public slots:
   void handleFeaturePermissionRequested(const QUrl &securityOrigin,
@@ -47,7 +44,7 @@ protected slots:
   void
   javaScriptConsoleMessage(WebEnginePage::JavaScriptConsoleMessageLevel level,
                            const QString &message, int lineId,
-                           const QString &sourceId);
+                           const QString &sourceId) override;
 private slots:
   void handleAuthenticationRequired(const QUrl &requestUrl,
                                     QAuthenticator *auth);
diff --git a/src/webview.cpp b/src/webview.cpp
index 8029ffd..035fb4b 100644
--- a/src/webview.cpp
+++ b/src/webview.cpp
@@ -7,8 +7,7 @@
 #include <mainwindow.h>
 
 WebView::WebView(QWidget *parent, QStringList dictionaries)
-    : QWebEngineView(parent) {
-  dictionaries = dictionaries;
+    : QWebEngineView(parent), m_dictionaries(dictionaries) {
 
   QObject *parentMainWindow = this->parent();
   while (!parentMainWindow->objectName().contains("MainWindow")) {
@@ -99,22 +98,24 @@ void WebView::contextMenuEvent(QContextMenuEvent *event) {
   spellcheckAction->setCheckable(true);
   spellcheckAction->setChecked(pageWebengineProfile->isSpellCheckEnabled());
   connect(spellcheckAction, &QAction::toggled, this,
-          [pageWebengineProfile, this](bool toogled) {
+          [pageWebengineProfile](bool toogled) {
             pageWebengineProfile->setSpellCheckEnabled(toogled);
-            settings.setValue("sc_enabled", toogled);
+            SettingsManager::instance().settings().setValue("sc_enabled",
+                                                            toogled);
           });
   menu->addAction(spellcheckAction);
 
   if (pageWebengineProfile->isSpellCheckEnabled()) {
     auto subMenu = menu->addMenu(tr("Select Language"));
-    for (const QString &dict : qAsConst(dictionaries)) {
+    for (const QString &dict : qAsConst(m_dictionaries)) {
       auto action = subMenu->addAction(dict);
       action->setCheckable(true);
       action->setChecked(languages.contains(dict));
-      connect(action, &QAction::triggered, this, [pageWebengineProfile, dict, this]() {
-        pageWebengineProfile->setSpellCheckLanguages(QStringList() << dict);
-        settings.setValue("sc_dict", dict);
-      });
+      connect(
+          action, &QAction::triggered, this, [pageWebengineProfile, dict]() {
+            pageWebengineProfile->setSpellCheckLanguages(QStringList() << dict);
+            SettingsManager::instance().settings().setValue("sc_dict", dict);
+          });
     }
   }
   connect(menu, &QMenu::aboutToHide, menu, &QObject::deleteLater);
diff --git a/src/webview.h b/src/webview.h
index e03fa49..058341d 100644
--- a/src/webview.h
+++ b/src/webview.h
@@ -1,9 +1,10 @@
 #ifndef WEBVIEW_H
 #define WEBVIEW_H
 
-#include <QSettings>
-#include <QWebEngineView>
 #include <QKeyEvent>
+#include <QWebEngineView>
+
+#include "settingsmanager.h"
 
 class WebView : public QWebEngineView {
   Q_OBJECT
@@ -13,13 +14,10 @@ public:
 
 protected:
   void contextMenuEvent(QContextMenuEvent *event) override;
-
-protected slots:
-  void wheelEvent(QWheelEvent *event);
+  void wheelEvent(QWheelEvent *event) override;
 
 private:
-  QStringList dictionaries;
-  QSettings settings;
+  QStringList m_dictionaries;
 };
 
 #endif // WEBVIEW_H
diff --git a/src/widgets/MoreApps/moreapps.cpp b/src/widgets/MoreApps/moreapps.cpp
index b8e8c17..c333751 100644
--- a/src/widgets/MoreApps/moreapps.cpp
+++ b/src/widgets/MoreApps/moreapps.cpp
@@ -11,6 +11,7 @@
 #include <algorithm>
 #include <cstdlib>
 #include <ctime>
+#include <random>
 
 MoreApps::MoreApps(QWidget *parent, QNetworkAccessManager *nam,
                    const QString &publisherName, const QUrl &remoteFilterUrl,
@@ -217,7 +218,7 @@ void MoreApps::setRemoteIcon(const QUrl &iconUrl, QLabel *lb) {
         auto replyBytes = reply->readAll();
         QPixmap pixmap;
         pixmap.loadFromData(replyBytes);
-        //qDebug() << "after load" << lb->size();
+        // qDebug() << "after load" << lb->size();
         lb->setPixmap(pixmap.scaled(lb->size(), Qt::KeepAspectRatio,
                                     Qt::SmoothTransformation));
       }
@@ -239,11 +240,10 @@ void MoreApps::showApps() {
 
   qDebug() << "showing apps...";
 
-  std::srand(unsigned(std::time(0)));
-  // rand generator
-  auto rand = [](auto i) { return std::rand() % i; };
-  // shuffle appList before adding
-  std::random_shuffle(mAppList.begin(), mAppList.end(), rand);
+  std::random_device rd;
+  std::mt19937 rng(rd());
+
+  std::shuffle(mAppList.begin(), mAppList.end(), rng);
 
   auto fallbackIconUrl =
       QUrl("https://dashboard.snapcraft.io/site_media/appmedia/"
@@ -254,7 +254,7 @@ void MoreApps::showApps() {
     setRemoteIcon(fallbackIconUrl, nullptr);
     foreach (auto a, mAppList) {
       auto iconUrl = a.getIconUrl();
-      //qDebug() << "pre-caching icon for" << a.getName();
+      // qDebug() << "pre-caching icon for" << a.getName();
       setRemoteIcon(iconUrl, nullptr);
     }
   }
diff --git a/src/widgets/scrolltext/scrolltext.cpp b/src/widgets/scrolltext/scrolltext.cpp
index b03b761..cac212f 100644
--- a/src/widgets/scrolltext/scrolltext.cpp
+++ b/src/widgets/scrolltext/scrolltext.cpp
@@ -15,7 +15,7 @@ ScrollText::ScrollText(QWidget *parent) : QWidget(parent), scrollPos(0) {
 
   setSeparator("        ");
 
-  connect(&timer, SIGNAL(timeout()), this, SLOT(timer_timeout()));
+  connect(&timer, &QTimer::timeout, this, &ScrollText::timer_timeout);
   timer.setInterval(50);
 }