diff --git a/examples/dialog/dialog.cpp b/examples/dialog/dialog.cpp
index b08abaf7..f4b8258d 100644
--- a/examples/dialog/dialog.cpp
+++ b/examples/dialog/dialog.cpp
@@ -97,12 +97,11 @@ void Dialog::setupUi()
 
     connect(moreButton, &QPushButton::toggled, extension, &QWidget::setVisible);
 
-    QVBoxLayout *extensionLayout = new QVBoxLayout;
+    QVBoxLayout *extensionLayout = new QVBoxLayout(extension);
     extensionLayout->setContentsMargins(0, 0, 0, 0);
     extensionLayout->addWidget(wholeWordsCheckBox);
     extensionLayout->addWidget(backwardCheckBox);
     extensionLayout->addWidget(searchSelectionCheckBox);
-    extension->setLayout(extensionLayout);
 
     QHBoxLayout *topLeftLayout = new QHBoxLayout;
     topLeftLayout->addWidget(label);
@@ -120,14 +119,12 @@ void Dialog::setupUi()
     controlsLayout->addWidget(extension, 1, 0, 1, 2);
     controlsLayout->setRowStretch(2, 1);
 
-    QVBoxLayout *mainLayout = new QVBoxLayout;
+    QVBoxLayout *mainLayout = new QVBoxLayout(this);
     mainLayout->setContentsMargins(0, 0, 0, 0);
     mainLayout->setSizeConstraint(QLayout::SetFixedSize);
     mainLayout->addWidget(titleBar);
     mainLayout->addLayout(controlsLayout);
 
-    setLayout(mainLayout);
-
     extension->hide();
 
     FramelessWidgetsHelper *helper = FramelessWidgetsHelper::get(this);
diff --git a/examples/openglwidget/mainwindow.cpp b/examples/openglwidget/mainwindow.cpp
index 87a13654..1679bdf3 100644
--- a/examples/openglwidget/mainwindow.cpp
+++ b/examples/openglwidget/mainwindow.cpp
@@ -73,7 +73,6 @@ void MainWindow::initialize()
     mainLayout->setContentsMargins(0, 0, 0, 0);
     mainLayout->addWidget(m_titleBar);
     mainLayout->addWidget(m_glWidget);
-    setLayout(mainLayout);
 
     FramelessWidgetsHelper *helper = FramelessWidgetsHelper::get(this);
     helper->setTitleBarWidget(m_titleBar);
diff --git a/examples/widget/widget.cpp b/examples/widget/widget.cpp
index c44b5116..826d9ca8 100644
--- a/examples/widget/widget.cpp
+++ b/examples/widget/widget.cpp
@@ -102,7 +102,6 @@ void Widget::initialize()
     mainLayout->setContentsMargins(0, 0, 0, 0);
     mainLayout->addWidget(m_titleBar);
     mainLayout->addLayout(contentLayout);
-    setLayout(mainLayout);
     updateStyleSheet();
 
     m_cancelShortcut = new QShortcut(this);
diff --git a/include/FramelessHelper/Widgets/private/framelessdialog_p.h b/include/FramelessHelper/Widgets/private/framelessdialog_p.h
index c36a06d0..66b0a964 100644
--- a/include/FramelessHelper/Widgets/private/framelessdialog_p.h
+++ b/include/FramelessHelper/Widgets/private/framelessdialog_p.h
@@ -44,14 +44,8 @@ class FRAMELESSHELPER_WIDGETS_API FramelessDialogPrivate : public QObject
     Q_NODISCARD static FramelessDialogPrivate *get(FramelessDialog *pub);
     Q_NODISCARD static const FramelessDialogPrivate *get(const FramelessDialog *pub);
 
-    Q_NODISCARD WidgetsSharedHelper *widgetsSharedHelper() const;
-
-private:
-    void initialize();
-
-private:
     FramelessDialog *q_ptr = nullptr;
-    WidgetsSharedHelper *m_sharedHelper = nullptr;
+    WidgetsSharedHelper *sharedHelper = nullptr;
 };
 
 FRAMELESSHELPER_END_NAMESPACE
diff --git a/include/FramelessHelper/Widgets/private/framelessmainwindow_p.h b/include/FramelessHelper/Widgets/private/framelessmainwindow_p.h
index fecf9e3b..f15ca176 100644
--- a/include/FramelessHelper/Widgets/private/framelessmainwindow_p.h
+++ b/include/FramelessHelper/Widgets/private/framelessmainwindow_p.h
@@ -44,21 +44,9 @@ class FRAMELESSHELPER_WIDGETS_API FramelessMainWindowPrivate : public QObject
     Q_NODISCARD static FramelessMainWindowPrivate *get(FramelessMainWindow *pub);
     Q_NODISCARD static const FramelessMainWindowPrivate *get(const FramelessMainWindow *pub);
 
-    Q_NODISCARD bool isNormal() const;
-    Q_NODISCARD bool isZoomed() const;
-
-    void toggleMaximized();
-    void toggleFullScreen();
-
-    Q_NODISCARD WidgetsSharedHelper *widgetsSharedHelper() const;
-
-private:
-    void initialize();
-
-private:
     FramelessMainWindow *q_ptr = nullptr;
-    Qt::WindowState m_savedWindowState = Qt::WindowNoState;
-    WidgetsSharedHelper *m_sharedHelper = nullptr;
+    Qt::WindowState savedWindowState = Qt::WindowNoState;
+    WidgetsSharedHelper *sharedHelper = nullptr;
 };
 
 FRAMELESSHELPER_END_NAMESPACE
diff --git a/include/FramelessHelper/Widgets/private/framelesswidget_p.h b/include/FramelessHelper/Widgets/private/framelesswidget_p.h
index 347172b4..4146011e 100644
--- a/include/FramelessHelper/Widgets/private/framelesswidget_p.h
+++ b/include/FramelessHelper/Widgets/private/framelesswidget_p.h
@@ -44,21 +44,9 @@ class FRAMELESSHELPER_WIDGETS_API FramelessWidgetPrivate : public QObject
     Q_NODISCARD static FramelessWidgetPrivate *get(FramelessWidget *pub);
     Q_NODISCARD static const FramelessWidgetPrivate *get(const FramelessWidget *pub);
 
-    Q_NODISCARD bool isNormal() const;
-    Q_NODISCARD bool isZoomed() const;
-
-    void toggleMaximized();
-    void toggleFullScreen();
-
-    Q_NODISCARD WidgetsSharedHelper *widgetsSharedHelper() const;
-
-private:
-    void initialize();
-
-private:
     FramelessWidget *q_ptr = nullptr;
-    Qt::WindowState m_savedWindowState = Qt::WindowNoState;
-    WidgetsSharedHelper *m_sharedHelper = nullptr;
+    Qt::WindowState savedWindowState = Qt::WindowNoState;
+    WidgetsSharedHelper *sharedHelper = nullptr;
 };
 
 FRAMELESSHELPER_END_NAMESPACE
diff --git a/include/FramelessHelper/Widgets/private/framelesswidgetshelper_p.h b/include/FramelessHelper/Widgets/private/framelesswidgetshelper_p.h
index 74c3f410..2f81b497 100644
--- a/include/FramelessHelper/Widgets/private/framelesswidgetshelper_p.h
+++ b/include/FramelessHelper/Widgets/private/framelesswidgetshelper_p.h
@@ -49,53 +49,25 @@ class FRAMELESSHELPER_WIDGETS_API FramelessWidgetsHelperPrivate : public QObject
     Q_NODISCARD static FramelessWidgetsHelperPrivate *get(FramelessWidgetsHelper *pub);
     Q_NODISCARD static const FramelessWidgetsHelperPrivate *get(const FramelessWidgetsHelper *pub);
 
-    Q_NODISCARD bool isContentExtendedIntoTitleBar() const;
-    void extendsContentIntoTitleBar(const bool value);
-
-    Q_NODISCARD QWidget *getTitleBarWidget() const;
-    void setTitleBarWidget(QWidget *widget);
-
     void attach();
     void detach();
-    void setSystemButton(QWidget *widget, const Global::SystemButtonType buttonType);
-    void setHitTestVisible(QWidget *widget, const bool visible = true);
-    void setHitTestVisible(const QRect &rect, const bool visible = true);
-    void setHitTestVisible(QObject *object, const bool visible = true);
-    void showSystemMenu(const QPoint &pos);
-    void windowStartSystemMove2(const QPoint &pos);
-    void windowStartSystemResize2(const Qt::Edges edges, const QPoint &pos);
-
-    void moveWindowToDesktopCenter();
-    void bringWindowToFront();
-
-    Q_NODISCARD bool isWindowFixedSize() const;
-    void setWindowFixedSize(const bool value);
 
     void emitSignalForAllInstances(const char *signal);
 
-    Q_NODISCARD bool isBlurBehindWindowEnabled() const;
-    void setBlurBehindWindowEnabled(const bool enable, const QColor &color);
-
     void setProperty(const char *name, const QVariant &value);
     Q_NODISCARD QVariant getProperty(const char *name, const QVariant &defaultValue = {});
 
-    Q_NODISCARD QWidget *window() const;
-
     Q_NODISCARD MicaMaterial *getMicaMaterialIfAny() const;
     Q_NODISCARD WindowBorderPainter *getWindowBorderIfAny() const;
 
     Q_NODISCARD static WidgetsSharedHelper *findOrCreateSharedHelper(QWidget *window);
     Q_NODISCARD static FramelessWidgetsHelper *findOrCreateFramelessHelper(QObject *object);
 
-    Q_NODISCARD bool isReady() const;
-    void waitForReady();
-
     void repaintAllChildren(const quint32 delay = 0) const;
 
     Q_NODISCARD quint32 readyWaitTime() const;
     void setReadyWaitTime(const quint32 time);
 
-private:
     Q_NODISCARD QRect mapWidgetGeometryToScene(const QWidget * const widget) const;
     Q_NODISCARD bool isInSystemButtons(const QPoint &pos, Global::SystemButtonType *button) const;
     Q_NODISCARD bool isInTitleBarDraggableArea(const QPoint &pos) const;
@@ -105,15 +77,13 @@ class FRAMELESSHELPER_WIDGETS_API FramelessWidgetsHelperPrivate : public QObject
     Q_NODISCARD const FramelessWidgetsHelperData *getWindowData() const;
     Q_NODISCARD FramelessWidgetsHelperData *getWindowDataMutable() const;
 
-private:
     FramelessWidgetsHelper *q_ptr = nullptr;
-    QColor m_savedWindowBackgroundColor = {};
-    bool m_blurBehindWindowEnabled = false;
-    QPointer<QWidget> m_window = nullptr;
-    bool m_destroying = false;
-    bool m_qpaReady = false;
-    QSizePolicy m_savedSizePolicy = {};
-    quint32 m_qpaWaitTime = 0;
+    QColor savedWindowBackgroundColor = {};
+    bool blurBehindWindowEnabled = false;
+    QPointer<QWidget> window = nullptr;
+    bool qpaReady = false;
+    QSizePolicy savedSizePolicy = {};
+    quint32 qpaWaitTime = 0;
 };
 
 FRAMELESSHELPER_END_NAMESPACE
diff --git a/include/FramelessHelper/Widgets/private/standardsystembutton_p.h b/include/FramelessHelper/Widgets/private/standardsystembutton_p.h
index f09996ad..91742d96 100644
--- a/include/FramelessHelper/Widgets/private/standardsystembutton_p.h
+++ b/include/FramelessHelper/Widgets/private/standardsystembutton_p.h
@@ -27,11 +27,6 @@
 #include <FramelessHelper/Widgets/framelesshelperwidgets_global.h>
 #include <optional>
 
-QT_BEGIN_NAMESPACE
-class QEnterEvent;
-class QPaintEvent;
-QT_END_NAMESPACE
-
 FRAMELESSHELPER_BEGIN_NAMESPACE
 
 class StandardSystemButton;
@@ -49,46 +44,18 @@ class FRAMELESSHELPER_WIDGETS_API StandardSystemButtonPrivate : public QObject
     Q_NODISCARD static StandardSystemButtonPrivate *get(StandardSystemButton *pub);
     Q_NODISCARD static const StandardSystemButtonPrivate *get(const StandardSystemButton *pub);
 
-    Q_NODISCARD QString getGlyph() const;
-    void setGlyph(const QString &value);
-
-    Q_NODISCARD Global::SystemButtonType getButtonType() const;
-    void setButtonType(const Global::SystemButtonType type);
-
-    Q_NODISCARD QSize getRecommendedButtonSize() const;
-
-    Q_NODISCARD QColor getHoverColor() const;
-    Q_NODISCARD QColor getPressColor() const;
-    Q_NODISCARD QColor getNormalColor() const;
-    Q_NODISCARD QColor getActiveForegroundColor() const;
-    Q_NODISCARD QColor getInactiveForegroundColor() const;
-    Q_NODISCARD bool isActive() const;
-    Q_NODISCARD int glyphSize() const;
-
-    void setHoverColor(const QColor &value);
-    void setPressColor(const QColor &value);
-    void setNormalColor(const QColor &value);
-    void setActiveForegroundColor(const QColor &value);
-    void setInactiveForegroundColor(const QColor &value);
-    void setActive(const bool value);
-    void setGlyphSize(const int value);
-
-    void paintEventHandler(QPaintEvent *event);
-
-private:
-    void initialize();
+    Q_NODISCARD static QSize getRecommendedButtonSize();
 
-private:
     StandardSystemButton *q_ptr = nullptr;
-    Global::SystemButtonType m_buttonType = Global::SystemButtonType::Unknown;
-    QString m_glyph = {};
-    QColor m_hoverColor = {};
-    QColor m_pressColor = {};
-    QColor m_normalColor = {};
-    QColor m_activeForegroundColor = {};
-    QColor m_inactiveForegroundColor = {};
-    bool m_active = false;
-    std::optional<int> m_glyphSize = std::nullopt;
+    Global::SystemButtonType buttonType = Global::SystemButtonType::Unknown;
+    QString glyph = {};
+    QColor hoverColor = {};
+    QColor pressColor = {};
+    QColor normalColor = {};
+    QColor activeForegroundColor = {};
+    QColor inactiveForegroundColor = {};
+    bool active = false;
+    std::optional<int> glyphSize = std::nullopt;
 };
 
 FRAMELESSHELPER_END_NAMESPACE
diff --git a/include/FramelessHelper/Widgets/private/standardtitlebar_p.h b/include/FramelessHelper/Widgets/private/standardtitlebar_p.h
index 8bffd0e8..b1fd794b 100644
--- a/include/FramelessHelper/Widgets/private/standardtitlebar_p.h
+++ b/include/FramelessHelper/Widgets/private/standardtitlebar_p.h
@@ -29,7 +29,6 @@
 #include <optional>
 
 QT_BEGIN_NAMESPACE
-class QPaintEvent;
 class QMouseEvent;
 QT_END_NAMESPACE
 
@@ -59,33 +58,6 @@ class FRAMELESSHELPER_WIDGETS_API StandardTitleBarPrivate : public QObject
     Q_NODISCARD static StandardTitleBarPrivate *get(StandardTitleBar *pub);
     Q_NODISCARD static const StandardTitleBarPrivate *get(const StandardTitleBar *pub);
 
-    Q_NODISCARD Qt::Alignment titleLabelAlignment() const;
-    void setTitleLabelAlignment(const Qt::Alignment value);
-
-    Q_NODISCARD bool isExtended() const;
-    void setExtended(const bool value);
-
-    Q_NODISCARD bool isHideWhenClose() const;
-    void setHideWhenClose(const bool value);
-
-    Q_NODISCARD ChromePalette *chromePalette() const;
-
-    void paintTitleBar(QPaintEvent *event);
-
-    Q_NODISCARD bool titleLabelVisible() const;
-    void setTitleLabelVisible(const bool value);
-
-    Q_NODISCARD QSize windowIconSize() const;
-    void setWindowIconSize(const QSize &value);
-
-    Q_NODISCARD bool windowIconVisible() const;
-    void setWindowIconVisible(const bool value);
-
-    Q_NODISCARD QFont titleFont() const;
-    void setTitleFont(const QFont &value);
-
-    Q_NODISCARD bool mouseEventHandler(QMouseEvent *event);
-
     Q_NODISCARD QRect windowIconRect() const;
     Q_NODISCARD bool windowIconVisible_real() const;
     Q_NODISCARD bool isInTitleBarIconArea(const QPoint &pos) const;
@@ -93,35 +65,34 @@ class FRAMELESSHELPER_WIDGETS_API StandardTitleBarPrivate : public QObject
     Q_NODISCARD QFont defaultFont() const;
     Q_NODISCARD FontMetrics titleLabelSize() const;
 
-public Q_SLOTS:
-    void updateMaximizeButton();
-    void updateTitleBarColor();
-    void updateChromeButtonColor();
-    void retranslateUi();
+    Q_SLOT void updateMaximizeButton();
+    Q_SLOT void updateTitleBarColor();
+    Q_SLOT void updateChromeButtonColor();
+    Q_SLOT void retranslateUi();
 
-protected:
-    Q_NODISCARD bool eventFilter(QObject *object, QEvent *event) override;
+    Q_NODISCARD bool mouseEventHandler(QMouseEvent *event);
 
-private:
     void initialize();
 
-private:
     StandardTitleBar *q_ptr = nullptr;
 #ifndef Q_OS_MACOS
-    StandardSystemButton *m_minimizeButton = nullptr;
-    StandardSystemButton *m_maximizeButton = nullptr;
-    StandardSystemButton *m_closeButton = nullptr;
+    StandardSystemButton *minimizeButton = nullptr;
+    StandardSystemButton *maximizeButton = nullptr;
+    StandardSystemButton *closeButton = nullptr;
 #endif // Q_OS_MACOS
-    QPointer<QWidget> m_window = nullptr;
-    bool m_extended = false;
-    Qt::Alignment m_labelAlignment = {};
-    bool m_hideWhenClose = false;
-    ChromePalette *m_chromePalette = nullptr;
-    bool m_titleLabelVisible = true;
-    std::optional<QSize> m_windowIconSize = std::nullopt;
-    bool m_windowIconVisible = false;
-    std::optional<QFont> m_titleFont = std::nullopt;
-    bool m_closeTriggered = false;
+    QPointer<QWidget> window = nullptr;
+    bool extended = false;
+    Qt::Alignment labelAlignment = {};
+    bool hideWhenClose = false;
+    ChromePalette *chromePalette = nullptr;
+    bool titleLabelVisible = true;
+    std::optional<QSize> windowIconSize = std::nullopt;
+    bool windowIconVisible = false;
+    std::optional<QFont> titleFont = std::nullopt;
+    bool closeTriggered = false;
+
+protected:
+    bool eventFilter(QObject *object, QEvent *event) override;
 };
 
 FRAMELESSHELPER_END_NAMESPACE
diff --git a/include/FramelessHelper/Widgets/standardsystembutton.h b/include/FramelessHelper/Widgets/standardsystembutton.h
index fc3412a8..16cf3695 100644
--- a/include/FramelessHelper/Widgets/standardsystembutton.h
+++ b/include/FramelessHelper/Widgets/standardsystembutton.h
@@ -52,7 +52,7 @@ class FRAMELESSHELPER_WIDGETS_API StandardSystemButton : public QPushButton
     ~StandardSystemButton() override;
 
     Q_NODISCARD QSize sizeHint() const override;
-    Q_NODISCARD Global::SystemButtonType buttonType();
+    Q_NODISCARD Global::SystemButtonType buttonType() const;
     Q_NODISCARD QString glyph() const;
     Q_NODISCARD QColor hoverColor() const;
     Q_NODISCARD QColor pressColor() const;
diff --git a/src/core/framelesshelper_win.cpp b/src/core/framelesshelper_win.cpp
index 4d98db9f..ffcb138e 100644
--- a/src/core/framelesshelper_win.cpp
+++ b/src/core/framelesshelper_win.cpp
@@ -988,6 +988,9 @@ bool FramelessHelperWin::nativeEventFilter(const QByteArray &eventType, void *me
 #endif
     case WM_NCMOUSEHOVER:
     case WM_NCMOUSELEAVE: {
+        // For future code readers:
+        // The following code is not workaround anything, it's just try to emulate the original
+        // behavior of a native Win32 window.
         const WindowPart previousWindowPart = getHittedWindowPart(data.hitTestResult.first.value_or(HTNOWHERE));
         const bool isXButtonMessage = ((uMsg >= WM_NCXBUTTONDOWN) && (uMsg <= WM_NCXBUTTONDBLCLK));
         const WindowPart nowWindowPart = getHittedWindowPart(isXButtonMessage ? GET_NCHITTEST_WPARAM(wParam) : wParam);
diff --git a/src/quick/framelessquickhelper.cpp b/src/quick/framelessquickhelper.cpp
index a0772025..2f4fa61c 100644
--- a/src/quick/framelessquickhelper.cpp
+++ b/src/quick/framelessquickhelper.cpp
@@ -237,7 +237,8 @@ void FramelessQuickHelperPrivate::setProperty(const char *name, const QVariant &
     Q_ASSERT(name);
     Q_ASSERT(*name != '\0');
     Q_ASSERT(value.isValid());
-    if (!name || (*name == '\0') || !value.isValid()) {
+    Q_ASSERT(!value.isNull());
+    if (!name || (*name == '\0') || !value.isValid() || value.isNull()) {
         return;
     }
     Q_Q(FramelessQuickHelper);
@@ -261,7 +262,7 @@ QVariant FramelessQuickHelperPrivate::getProperty(const char *name, const QVaria
         return {};
     }
     const QVariant value = window->property(name);
-    return (value.isValid() ? value : defaultValue);
+    return ((value.isValid() && !value.isNull()) ? value : defaultValue);
 }
 
 QuickMicaMaterial *FramelessQuickHelperPrivate::findOrCreateMicaMaterial() const
diff --git a/src/widgets/framelessdialog.cpp b/src/widgets/framelessdialog.cpp
index 49ba0c03..a6a634d9 100644
--- a/src/widgets/framelessdialog.cpp
+++ b/src/widgets/framelessdialog.cpp
@@ -26,7 +26,6 @@
 #include "framelessdialog_p.h"
 #include "framelesswidgetshelper.h"
 #include "widgetssharedhelper_p.h"
-#include <FramelessHelper/Core/utils.h>
 #include <QtCore/qloggingcategory.h>
 
 FRAMELESSHELPER_BEGIN_NAMESPACE
@@ -54,7 +53,6 @@ FramelessDialogPrivate::FramelessDialogPrivate(FramelessDialog *q) : QObject(q)
         return;
     }
     q_ptr = q;
-    initialize();
 }
 
 FramelessDialogPrivate::~FramelessDialogPrivate() = default;
@@ -77,22 +75,13 @@ const FramelessDialogPrivate *FramelessDialogPrivate::get(const FramelessDialog
     return pub->d_func();
 }
 
-void FramelessDialogPrivate::initialize()
-{
-    Q_Q(FramelessDialog);
-    FramelessWidgetsHelper::get(q)->extendsContentIntoTitleBar();
-    m_sharedHelper = new WidgetsSharedHelper(this);
-    m_sharedHelper->setup(q);
-}
-
-WidgetsSharedHelper *FramelessDialogPrivate::widgetsSharedHelper() const
-{
-    return m_sharedHelper;
-}
-
 FramelessDialog::FramelessDialog(QWidget *parent)
     : QDialog(parent), d_ptr(new FramelessDialogPrivate(this))
 {
+    FramelessWidgetsHelper::get(this)->extendsContentIntoTitleBar();
+    Q_D(FramelessDialog);
+    d->sharedHelper = new WidgetsSharedHelper(d);
+    d->sharedHelper->setup(this);
 }
 
 FramelessDialog::~FramelessDialog() = default;
diff --git a/src/widgets/framelessmainwindow.cpp b/src/widgets/framelessmainwindow.cpp
index 41c309f5..5131a764 100644
--- a/src/widgets/framelessmainwindow.cpp
+++ b/src/widgets/framelessmainwindow.cpp
@@ -54,7 +54,6 @@ FramelessMainWindowPrivate::FramelessMainWindowPrivate(FramelessMainWindow *q) :
         return;
     }
     q_ptr = q;
-    initialize();
 }
 
 FramelessMainWindowPrivate::~FramelessMainWindowPrivate() = default;
@@ -77,81 +76,45 @@ const FramelessMainWindowPrivate *FramelessMainWindowPrivate::get(const Frameles
     return pub->d_func();
 }
 
-void FramelessMainWindowPrivate::initialize()
-{
-    Q_Q(FramelessMainWindow);
-    FramelessWidgetsHelper::get(q)->extendsContentIntoTitleBar();
-    m_sharedHelper = new WidgetsSharedHelper(this);
-    m_sharedHelper->setup(q);
-}
-
-bool FramelessMainWindowPrivate::isNormal() const
-{
-    Q_Q(const FramelessMainWindow);
-    return (Utils::windowStatesToWindowState(q->windowState()) == Qt::WindowNoState);
-}
-
-bool FramelessMainWindowPrivate::isZoomed() const
-{
-    Q_Q(const FramelessMainWindow);
-    return (q->isMaximized() || q->isFullScreen());
-}
-
-void FramelessMainWindowPrivate::toggleMaximized()
-{
-    Q_Q(FramelessMainWindow);
-    if (q->isMaximized()) {
-        q->showNormal();
-    } else {
-        q->showMaximized();
-    }
-}
-
-void FramelessMainWindowPrivate::toggleFullScreen()
-{
-    Q_Q(FramelessMainWindow);
-    if (q->isFullScreen()) {
-        q->setWindowState(m_savedWindowState);
-    } else {
-        m_savedWindowState = Utils::windowStatesToWindowState(q->windowState());
-        q->showFullScreen();
-    }
-}
-
-WidgetsSharedHelper *FramelessMainWindowPrivate::widgetsSharedHelper() const
-{
-    return m_sharedHelper;
-}
-
 FramelessMainWindow::FramelessMainWindow(QWidget *parent, const Qt::WindowFlags flags)
     : QMainWindow(parent, flags), d_ptr(new FramelessMainWindowPrivate(this))
 {
+    FramelessWidgetsHelper::get(this)->extendsContentIntoTitleBar();
+    Q_D(FramelessMainWindow);
+    d->sharedHelper = new WidgetsSharedHelper(d);
+    d->sharedHelper->setup(this);
 }
 
 FramelessMainWindow::~FramelessMainWindow() = default;
 
 bool FramelessMainWindow::isNormal() const
 {
-    Q_D(const FramelessMainWindow);
-    return d->isNormal();
+    return (Utils::windowStatesToWindowState(windowState()) == Qt::WindowNoState);
 }
 
 bool FramelessMainWindow::isZoomed() const
 {
-    Q_D(const FramelessMainWindow);
-    return d->isZoomed();
+    return (isMaximized() || isFullScreen());
 }
 
 void FramelessMainWindow::toggleMaximized()
 {
-    Q_D(FramelessMainWindow);
-    d->toggleMaximized();
+    if (isMaximized()) {
+        showNormal();
+    } else {
+        showMaximized();
+    }
 }
 
 void FramelessMainWindow::toggleFullScreen()
 {
     Q_D(FramelessMainWindow);
-    d->toggleFullScreen();
+    if (isFullScreen()) {
+        setWindowState(d->savedWindowState);
+    } else {
+        d->savedWindowState = Utils::windowStatesToWindowState(windowState());
+        showFullScreen();
+    }
 }
 
 FRAMELESSHELPER_END_NAMESPACE
diff --git a/src/widgets/framelesswidget.cpp b/src/widgets/framelesswidget.cpp
index 7ce4feb9..72e40a26 100644
--- a/src/widgets/framelesswidget.cpp
+++ b/src/widgets/framelesswidget.cpp
@@ -54,7 +54,6 @@ FramelessWidgetPrivate::FramelessWidgetPrivate(FramelessWidget *q) : QObject(q)
         return;
     }
     q_ptr = q;
-    initialize();
 }
 
 FramelessWidgetPrivate::~FramelessWidgetPrivate() = default;
@@ -77,81 +76,45 @@ const FramelessWidgetPrivate *FramelessWidgetPrivate::get(const FramelessWidget
     return pub->d_func();
 }
 
-void FramelessWidgetPrivate::initialize()
-{
-    Q_Q(FramelessWidget);
-    FramelessWidgetsHelper::get(q)->extendsContentIntoTitleBar();
-    m_sharedHelper = new WidgetsSharedHelper(this);
-    m_sharedHelper->setup(q);
-}
-
-bool FramelessWidgetPrivate::isNormal() const
-{
-    Q_Q(const FramelessWidget);
-    return (Utils::windowStatesToWindowState(q->windowState()) == Qt::WindowNoState);
-}
-
-bool FramelessWidgetPrivate::isZoomed() const
-{
-    Q_Q(const FramelessWidget);
-    return (q->isMaximized() || q->isFullScreen());
-}
-
-void FramelessWidgetPrivate::toggleMaximized()
-{
-    Q_Q(FramelessWidget);
-    if (q->isMaximized()) {
-        q->showNormal();
-    } else {
-        q->showMaximized();
-    }
-}
-
-void FramelessWidgetPrivate::toggleFullScreen()
-{
-    Q_Q(FramelessWidget);
-    if (q->isFullScreen()) {
-        q->setWindowState(m_savedWindowState);
-    } else {
-        m_savedWindowState = Utils::windowStatesToWindowState(q->windowState());
-        q->showFullScreen();
-    }
-}
-
-WidgetsSharedHelper *FramelessWidgetPrivate::widgetsSharedHelper() const
-{
-    return m_sharedHelper;
-}
-
 FramelessWidget::FramelessWidget(QWidget *parent)
     : QWidget(parent, Qt::Window),  d_ptr(new FramelessWidgetPrivate(this))
 {
+    FramelessWidgetsHelper::get(this)->extendsContentIntoTitleBar();
+    Q_D(FramelessWidget);
+    d->sharedHelper = new WidgetsSharedHelper(d);
+    d->sharedHelper->setup(this);
 }
 
 FramelessWidget::~FramelessWidget() = default;
 
 bool FramelessWidget::isNormal() const
 {
-    Q_D(const FramelessWidget);
-    return d->isNormal();
+    return (Utils::windowStatesToWindowState(windowState()) == Qt::WindowNoState);
 }
 
 bool FramelessWidget::isZoomed() const
 {
-    Q_D(const FramelessWidget);
-    return d->isZoomed();
+    return (isMaximized() || isFullScreen());
 }
 
 void FramelessWidget::toggleMaximized()
 {
-    Q_D(FramelessWidget);
-    d->toggleMaximized();
+    if (isMaximized()) {
+        showNormal();
+    } else {
+        showMaximized();
+    }
 }
 
 void FramelessWidget::toggleFullScreen()
 {
     Q_D(FramelessWidget);
-    d->toggleFullScreen();
+    if (isFullScreen()) {
+        setWindowState(d->savedWindowState);
+    } else {
+        d->savedWindowState = Utils::windowStatesToWindowState(windowState());
+        showFullScreen();
+    }
 }
 
 FRAMELESSHELPER_END_NAMESPACE
diff --git a/src/widgets/framelesswidgetshelper.cpp b/src/widgets/framelesswidgetshelper.cpp
index b1896d26..eb914314 100644
--- a/src/widgets/framelesswidgetshelper.cpp
+++ b/src/widgets/framelesswidgetshelper.cpp
@@ -169,11 +169,7 @@ FramelessWidgetsHelperPrivate::FramelessWidgetsHelperPrivate(FramelessWidgetsHel
     q_ptr = q;
 }
 
-FramelessWidgetsHelperPrivate::~FramelessWidgetsHelperPrivate()
-{
-    m_destroying = true;
-    extendsContentIntoTitleBar(false);
-}
+FramelessWidgetsHelperPrivate::~FramelessWidgetsHelperPrivate() = default;
 
 FramelessWidgetsHelperPrivate *FramelessWidgetsHelperPrivate::get(FramelessWidgetsHelper *pub)
 {
@@ -193,37 +189,6 @@ const FramelessWidgetsHelperPrivate *FramelessWidgetsHelperPrivate::get(const Fr
     return pub->d_func();
 }
 
-bool FramelessWidgetsHelperPrivate::isWindowFixedSize() const
-{
-    if (!m_window) {
-        return false;
-    }
-    return isWidgetFixedSize(m_window);
-}
-
-void FramelessWidgetsHelperPrivate::setWindowFixedSize(const bool value)
-{
-    if (!m_window) {
-        return;
-    }
-    if (isWindowFixedSize() == value) {
-        return;
-    }
-    if (value) {
-        m_savedSizePolicy = m_window->sizePolicy();
-        m_window->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
-        m_window->setFixedSize(m_window->size());
-    } else {
-        m_window->setSizePolicy(m_savedSizePolicy);
-        m_window->setMinimumSize(kDefaultWindowSize);
-        m_window->setMaximumSize(QSize(QWIDGETSIZE_MAX, QWIDGETSIZE_MAX));
-    }
-#ifdef Q_OS_WINDOWS
-    std::ignore = Utils::setAeroSnappingEnabled(m_window->winId(), !value);
-#endif
-    emitSignalForAllInstances("windowFixedSizeChanged");
-}
-
 void FramelessWidgetsHelperPrivate::emitSignalForAllInstances(const char *signal)
 {
     Q_ASSERT(signal);
@@ -231,10 +196,10 @@ void FramelessWidgetsHelperPrivate::emitSignalForAllInstances(const char *signal
     if (!signal || (*signal == '\0')) {
         return;
     }
-    if (!m_window) {
+    if (!window) {
         return;
     }
-    const auto instances = m_window->findChildren<FramelessWidgetsHelper *>();
+    const auto instances = window->findChildren<FramelessWidgetsHelper *>();
     if (instances.isEmpty()) {
         return;
     }
@@ -243,57 +208,20 @@ void FramelessWidgetsHelperPrivate::emitSignalForAllInstances(const char *signal
     }
 }
 
-bool FramelessWidgetsHelperPrivate::isBlurBehindWindowEnabled() const
-{
-    return m_blurBehindWindowEnabled;
-}
-
-void FramelessWidgetsHelperPrivate::setBlurBehindWindowEnabled(const bool enable, const QColor &color)
-{
-    if (!m_window) {
-        return;
-    }
-    if (m_blurBehindWindowEnabled == enable) {
-        return;
-    }
-    if (Utils::isBlurBehindWindowSupported()) {
-        QPalette palette = m_window->palette();
-        if (enable) {
-            m_savedWindowBackgroundColor = palette.color(QPalette::Window);
-        }
-        palette.setColor(QPalette::Window, (enable ? kDefaultTransparentColor : m_savedWindowBackgroundColor));
-        m_window->setPalette(palette);
-        if (Utils::setBlurBehindWindowEnabled(m_window->winId(),
-               (enable ? BlurMode::Default : BlurMode::Disable), color)) {
-            m_blurBehindWindowEnabled = enable;
-            emitSignalForAllInstances("blurBehindWindowEnabledChanged");
-        } else {
-            WARNING << "Failed to enable/disable blur behind window.";
-        }
-    } else {
-        if (WidgetsSharedHelper * const helper = findOrCreateSharedHelper(m_window)) {
-            m_blurBehindWindowEnabled = enable;
-            helper->setMicaEnabled(m_blurBehindWindowEnabled);
-            emitSignalForAllInstances("blurBehindWindowEnabledChanged");
-        } else {
-            DEBUG << "Blur behind window is not supported on current platform.";
-        }
-    }
-}
-
 void FramelessWidgetsHelperPrivate::setProperty(const char *name, const QVariant &value)
 {
     Q_ASSERT(name);
     Q_ASSERT(*name != '\0');
     Q_ASSERT(value.isValid());
-    if (!name || (*name == '\0') || !value.isValid()) {
+    Q_ASSERT(!value.isNull());
+    if (!name || (*name == '\0') || !value.isValid() || value.isNull()) {
         return;
     }
-    Q_ASSERT(m_window);
-    if (!m_window) {
+    Q_ASSERT(window);
+    if (!window) {
         return;
     }
-    m_window->setProperty(name, value);
+    window->setProperty(name, value);
 }
 
 QVariant FramelessWidgetsHelperPrivate::getProperty(const char *name, const QVariant &defaultValue)
@@ -303,25 +231,20 @@ QVariant FramelessWidgetsHelperPrivate::getProperty(const char *name, const QVar
     if (!name || (*name == '\0')) {
         return {};
     }
-    Q_ASSERT(m_window);
-    if (!m_window) {
+    Q_ASSERT(window);
+    if (!window) {
         return {};
     }
-    const QVariant value = m_window->property(name);
-    return (value.isValid() ? value : defaultValue);
-}
-
-QWidget *FramelessWidgetsHelperPrivate::window() const
-{
-    return m_window;
+    const QVariant value = window->property(name);
+    return ((value.isValid() && !value.isNull()) ? value : defaultValue);
 }
 
 MicaMaterial *FramelessWidgetsHelperPrivate::getMicaMaterialIfAny() const
 {
-    if (!m_window) {
+    if (!window) {
         return nullptr;
     }
-    if (const WidgetsSharedHelper * const helper = findOrCreateSharedHelper(m_window)) {
+    if (const WidgetsSharedHelper * const helper = findOrCreateSharedHelper(window)) {
         return helper->rawMicaMaterial();
     }
     return nullptr;
@@ -329,10 +252,10 @@ MicaMaterial *FramelessWidgetsHelperPrivate::getMicaMaterialIfAny() const
 
 WindowBorderPainter *FramelessWidgetsHelperPrivate::getWindowBorderIfAny() const
 {
-    if (!m_window) {
+    if (!window) {
         return nullptr;
     }
-    if (const WidgetsSharedHelper * const helper = findOrCreateSharedHelper(m_window)) {
+    if (const WidgetsSharedHelper * const helper = findOrCreateSharedHelper(window)) {
         return helper->rawWindowBorder();
     }
     return nullptr;
@@ -346,17 +269,17 @@ WidgetsSharedHelper *FramelessWidgetsHelperPrivate::findOrCreateSharedHelper(QWi
     }
     if (const auto widget = qobject_cast<FramelessWidget *>(window)) {
         if (const auto widgetPriv = FramelessWidgetPrivate::get(widget)) {
-            return widgetPriv->widgetsSharedHelper();
+            return widgetPriv->sharedHelper;
         }
     }
     if (const auto mainWindow = qobject_cast<FramelessMainWindow *>(window)) {
         if (const auto mainWindowPriv = FramelessMainWindowPrivate::get(mainWindow)) {
-            return mainWindowPriv->widgetsSharedHelper();
+            return mainWindowPriv->sharedHelper;
         }
     }
     if (const auto dialog = qobject_cast<FramelessDialog *>(window)) {
         if (const auto dialogPriv = FramelessDialogPrivate::get(dialog)) {
-            return dialogPriv->widgetsSharedHelper();
+            return dialogPriv->sharedHelper;
         }
     }
     QWidget * const topLevelWindow = window->window();
@@ -391,38 +314,14 @@ FramelessWidgetsHelper *FramelessWidgetsHelperPrivate::findOrCreateFramelessHelp
     return instance;
 }
 
-bool FramelessWidgetsHelperPrivate::isReady() const
-{
-    return m_qpaReady;
-}
-
-void FramelessWidgetsHelperPrivate::waitForReady()
-{
-    if (m_qpaReady) {
-        return;
-    }
-#if 1
-    QEventLoop loop;
-    Q_Q(FramelessWidgetsHelper);
-    const QMetaObject::Connection connection = connect(
-        q, &FramelessWidgetsHelper::ready, &loop, &QEventLoop::quit);
-    loop.exec();
-    disconnect(connection);
-#else
-    while (!m_qpaReady) {
-        QCoreApplication::processEvents();
-    }
-#endif
-}
-
 void FramelessWidgetsHelperPrivate::repaintAllChildren(const quint32 delay) const
 {
-    if (!m_window) {
+    if (!window) {
         return;
     }
     const auto update = [this]() -> void {
-        forceWidgetRepaint(m_window);
-        const QList<QWidget *> widgets = m_window->findChildren<QWidget *>();
+        forceWidgetRepaint(window);
+        const QList<QWidget *> widgets = window->findChildren<QWidget *>();
         if (widgets.isEmpty()) {
             return;
         }
@@ -439,102 +338,28 @@ void FramelessWidgetsHelperPrivate::repaintAllChildren(const quint32 delay) cons
 
 quint32 FramelessWidgetsHelperPrivate::readyWaitTime() const
 {
-    return m_qpaWaitTime;
+    return qpaWaitTime;
 }
 
 void FramelessWidgetsHelperPrivate::setReadyWaitTime(const quint32 time)
 {
-    if (m_qpaWaitTime == time) {
-        return;
-    }
-    m_qpaWaitTime = time;
-}
-
-bool FramelessWidgetsHelperPrivate::isContentExtendedIntoTitleBar() const
-{
-    const FramelessWidgetsHelperData *data = getWindowData();
-    return (data ? data->ready : false);
-}
-
-void FramelessWidgetsHelperPrivate::setTitleBarWidget(QWidget *widget)
-{
-    Q_ASSERT(widget);
-    if (!widget) {
-        return;
-    }
-    FramelessWidgetsHelperData *data = getWindowDataMutable();
-    if (!data || (data->titleBarWidget == widget)) {
-        return;
-    }
-    data->titleBarWidget = widget;
-    emitSignalForAllInstances("titleBarWidgetChanged");
-}
-
-QWidget *FramelessWidgetsHelperPrivate::getTitleBarWidget() const
-{
-    const FramelessWidgetsHelperData *data = getWindowData();
-    return (data ? data->titleBarWidget : nullptr);
-}
-
-void FramelessWidgetsHelperPrivate::setHitTestVisible(QWidget *widget, const bool visible)
-{
-    Q_ASSERT(widget);
-    if (!widget) {
-        return;
-    }
-    FramelessWidgetsHelperData *data = getWindowDataMutable();
-    if (!data) {
+    if (qpaWaitTime == time) {
         return;
     }
-    if (visible) {
-        data->hitTestVisibleWidgets.append(widget);
-    } else {
-        data->hitTestVisibleWidgets.removeAll(widget);
-    }
-}
-
-void FramelessWidgetsHelperPrivate::setHitTestVisible(const QRect &rect, const bool visible)
-{
-    Q_ASSERT(rect.isValid());
-    if (!rect.isValid()) {
-        return;
-    }
-    FramelessWidgetsHelperData *data = getWindowDataMutable();
-    if (!data) {
-        return;
-    }
-    if (visible) {
-        data->hitTestVisibleRects.append(rect);
-    } else {
-        data->hitTestVisibleRects.removeAll(rect);
-    }
-}
-
-void FramelessWidgetsHelperPrivate::setHitTestVisible(QObject *object, const bool visible)
-{
-    Q_ASSERT(object);
-    if (!object) {
-        return;
-    }
-    const auto widget = qobject_cast<QWidget *>(object);
-    Q_ASSERT(widget);
-    if (!widget) {
-        return;
-    }
-    setHitTestVisible(widget, visible);
+    qpaWaitTime = time;
 }
 
 void FramelessWidgetsHelperPrivate::attach()
 {
-    QWidget * const window = findTopLevelWindow();
-    Q_ASSERT(window);
-    if (!window) {
+    QWidget * const tlw = findTopLevelWindow();
+    Q_ASSERT(tlw);
+    if (!tlw) {
         return;
     }
-    if (m_window == window) {
+    if (window == tlw) {
         return;
     }
-    m_window = window;
+    window = tlw;
 
     if (!window->testAttribute(Qt::WA_DontCreateNativeAncestors)) {
         window->setAttribute(Qt::WA_DontCreateNativeAncestors);
@@ -548,39 +373,41 @@ void FramelessWidgetsHelperPrivate::attach()
         return;
     }
 
+    Q_Q(FramelessWidgetsHelper);
+
     SystemParameters params = {};
-    params.getWindowId = [window]() -> WId { return window->winId(); };
-    params.getWindowFlags = [window]() -> Qt::WindowFlags { return window->windowFlags(); };
-    params.setWindowFlags = [window](const Qt::WindowFlags flags) -> void { window->setWindowFlags(flags); };
-    params.getWindowSize = [window]() -> QSize { return window->size(); };
-    params.setWindowSize = [window](const QSize &size) -> void { window->resize(size); };
-    params.getWindowPosition = [window]() -> QPoint { return window->pos(); };
-    params.setWindowPosition = [window](const QPoint &pos) -> void { window->move(pos); };
-    params.getWindowScreen = [window]() -> QScreen * {
+    params.getWindowId = [this]() -> WId { return window->winId(); };
+    params.getWindowFlags = [this]() -> Qt::WindowFlags { return window->windowFlags(); };
+    params.setWindowFlags = [this](const Qt::WindowFlags flags) -> void { window->setWindowFlags(flags); };
+    params.getWindowSize = [this]() -> QSize { return window->size(); };
+    params.setWindowSize = [this](const QSize &size) -> void { window->resize(size); };
+    params.getWindowPosition = [this]() -> QPoint { return window->pos(); };
+    params.setWindowPosition = [this](const QPoint &pos) -> void { window->move(pos); };
+    params.getWindowScreen = [this]() -> QScreen * {
 #if (QT_VERSION >= QT_VERSION_CHECK(5, 14, 0))
         return window->screen();
 #else
         return window->windowHandle()->screen();
 #endif
     };
-    params.isWindowFixedSize = [this]() -> bool { return isWindowFixedSize(); };
-    params.setWindowFixedSize = [this](const bool value) -> void { setWindowFixedSize(value); };
-    params.getWindowState = [window]() -> Qt::WindowState { return Utils::windowStatesToWindowState(window->windowState()); };
-    params.setWindowState = [window](const Qt::WindowState state) -> void { window->setWindowState(state); };
-    params.getWindowHandle = [window]() -> QWindow * { return window->windowHandle(); };
-    params.windowToScreen = [window](const QPoint &pos) -> QPoint { return window->mapToGlobal(pos); };
-    params.screenToWindow = [window](const QPoint &pos) -> QPoint { return window->mapFromGlobal(pos); };
+    params.isWindowFixedSize = [q]() -> bool { return q->isWindowFixedSize(); };
+    params.setWindowFixedSize = [q](const bool value) -> void { q->setWindowFixedSize(value); };
+    params.getWindowState = [this]() -> Qt::WindowState { return Utils::windowStatesToWindowState(window->windowState()); };
+    params.setWindowState = [this](const Qt::WindowState state) -> void { window->setWindowState(state); };
+    params.getWindowHandle = [this]() -> QWindow * { return window->windowHandle(); };
+    params.windowToScreen = [this](const QPoint &pos) -> QPoint { return window->mapToGlobal(pos); };
+    params.screenToWindow = [this](const QPoint &pos) -> QPoint { return window->mapFromGlobal(pos); };
     params.isInsideSystemButtons = [this](const QPoint &pos, SystemButtonType *button) -> bool { return isInSystemButtons(pos, button); };
     params.isInsideTitleBarDraggableArea = [this](const QPoint &pos) -> bool { return isInTitleBarDraggableArea(pos); };
-    params.getWindowDevicePixelRatio = [window]() -> qreal { return window->devicePixelRatioF(); };
+    params.getWindowDevicePixelRatio = [this]() -> qreal { return window->devicePixelRatioF(); };
     params.setSystemButtonState = [this](const SystemButtonType button, const ButtonState state) -> void { setSystemButtonState(button, state); };
     params.shouldIgnoreMouseEvents = [this](const QPoint &pos) -> bool { return shouldIgnoreMouseEvents(pos); };
-    params.showSystemMenu = [this](const QPoint &pos) -> void { showSystemMenu(pos); };
+    params.showSystemMenu = [q](const QPoint &pos) -> void { q->showSystemMenu(pos); };
     params.setProperty = [this](const char *name, const QVariant &value) -> void { setProperty(name, value); };
     params.getProperty = [this](const char *name, const QVariant &defaultValue) -> QVariant { return getProperty(name, defaultValue); };
-    params.setCursor = [window](const QCursor &cursor) -> void { window->setCursor(cursor); };
-    params.unsetCursor = [window]() -> void { window->unsetCursor(); };
-    params.getWidgetHandle = [window]() -> QObject * { return window; };
+    params.setCursor = [this](const QCursor &cursor) -> void { window->setCursor(cursor); };
+    params.unsetCursor = [this]() -> void { window->unsetCursor(); };
+    params.getWidgetHandle = [this]() -> QObject * { return window; };
     params.forceChildrenRepaint = [this](const int delay) -> void { repaintAllChildren(delay); };
     params.resetQtGrabbedControl = []() -> void { qt_button_down = nullptr; };
 
@@ -594,13 +421,13 @@ void FramelessWidgetsHelperPrivate::attach()
     // we reach here, and all the modifications from the Qt side will be lost
     // due to QPA will reset the position and size of the window during it's
     // initialization process.
-    QTimer::singleShot(m_qpaWaitTime, this, [this](){
-        m_qpaReady = true;
+    QTimer::singleShot(qpaWaitTime, this, [this, q](){
+        qpaReady = true;
         if (FramelessConfig::instance()->isSet(Option::CenterWindowBeforeShow)) {
-            moveWindowToDesktopCenter();
+            q->moveWindowToDesktopCenter();
         }
         if (FramelessConfig::instance()->isSet(Option::EnableBlurBehindWindow)) {
-            setBlurBehindWindowEnabled(true, {});
+            q->setBlurBehindWindowEnabled(true);
         }
         emitSignalForAllInstances("windowChanged");
         emitSignalForAllInstances("ready");
@@ -609,35 +436,20 @@ void FramelessWidgetsHelperPrivate::attach()
 
 void FramelessWidgetsHelperPrivate::detach()
 {
-    if (!m_window) {
+    if (!window) {
         return;
     }
-    const WId windowId = m_window->winId();
+    const WId windowId = window->winId();
     const auto it = g_framelessWidgetsHelperData()->constFind(windowId);
     if (it == g_framelessWidgetsHelperData()->constEnd()) {
         return;
     }
     g_framelessWidgetsHelperData()->erase(it);
     FramelessManager::instance()->removeWindow(windowId);
-    m_window = nullptr;
+    window = nullptr;
     emitSignalForAllInstances("windowChanged");
 }
 
-void FramelessWidgetsHelperPrivate::extendsContentIntoTitleBar(const bool value)
-{
-    if (isContentExtendedIntoTitleBar() == value) {
-        return;
-    }
-    if (value) {
-        attach();
-    } else {
-        detach();
-    }
-    if (!m_destroying) {
-        emitSignalForAllInstances("extendsContentIntoTitleBarChanged");
-    }
-}
-
 QWidget *FramelessWidgetsHelperPrivate::findTopLevelWindow() const
 {
     Q_Q(const FramelessWidgetsHelper);
@@ -653,11 +465,11 @@ QWidget *FramelessWidgetsHelperPrivate::findTopLevelWindow() const
 
 const FramelessWidgetsHelperData *FramelessWidgetsHelperPrivate::getWindowData() const
 {
-    //Q_ASSERT(m_window);
-    if (!m_window) {
+    //Q_ASSERT(window);
+    if (!window) {
         return nullptr;
     }
-    const WId windowId = m_window->winId();
+    const WId windowId = window->winId();
     auto it = g_framelessWidgetsHelperData()->find(windowId);
     if (it == g_framelessWidgetsHelperData()->end()) {
         it = g_framelessWidgetsHelperData()->insert(windowId, {});
@@ -667,11 +479,11 @@ const FramelessWidgetsHelperData *FramelessWidgetsHelperPrivate::getWindowData()
 
 FramelessWidgetsHelperData *FramelessWidgetsHelperPrivate::getWindowDataMutable() const
 {
-    //Q_ASSERT(m_window);
-    if (!m_window) {
+    //Q_ASSERT(window);
+    if (!window) {
         return nullptr;
     }
-    const WId windowId = m_window->winId();
+    const WId windowId = window->winId();
     auto it = g_framelessWidgetsHelperData()->find(windowId);
     if (it == g_framelessWidgetsHelperData()->end()) {
         it = g_framelessWidgetsHelperData()->insert(windowId, {});
@@ -685,10 +497,10 @@ QRect FramelessWidgetsHelperPrivate::mapWidgetGeometryToScene(const QWidget * co
     if (!widget) {
         return {};
     }
-    if (!m_window) {
+    if (!window) {
         return {};
     }
-    const QPoint originPoint = widget->mapTo(m_window, QPoint(0, 0));
+    const QPoint originPoint = widget->mapTo(window, QPoint(0, 0));
     const QSize size = widget->size();
     return QRect(originPoint, size);
 }
@@ -751,12 +563,12 @@ bool FramelessWidgetsHelperPrivate::isInTitleBarDraggableArea(const QPoint &pos)
         // The title bar is hidden or disabled for some reason, treat it as there's no title bar.
         return false;
     }
-    if (!m_window) {
+    if (!window) {
         // The FramelessWidgetsHelper object has not been attached to a specific window yet,
         // so we assume there's no title bar.
         return false;
     }
-    const QRect windowRect = {QPoint(0, 0), m_window->size()};
+    const QRect windowRect = {QPoint(0, 0), window->size()};
     const QRect titleBarRect = mapWidgetGeometryToScene(data->titleBarWidget);
     if (!titleBarRect.intersects(windowRect)) {
         // The title bar is totally outside of the window for some reason,
@@ -793,7 +605,7 @@ bool FramelessWidgetsHelperPrivate::isInTitleBarDraggableArea(const QPoint &pos)
 
 bool FramelessWidgetsHelperPrivate::shouldIgnoreMouseEvents(const QPoint &pos) const
 {
-    if (!m_window) {
+    if (!window) {
         return false;
     }
     const auto withinFrameBorder = [this, &pos]() -> bool {
@@ -806,9 +618,9 @@ bool FramelessWidgetsHelperPrivate::shouldIgnoreMouseEvents(const QPoint &pos) c
         }
 #endif
         return ((pos.x() < kDefaultResizeBorderThickness)
-                || (pos.x() >= (m_window->width() - kDefaultResizeBorderThickness)));
+                || (pos.x() >= (window->width() - kDefaultResizeBorderThickness)));
     }();
-    return ((Utils::windowStatesToWindowState(m_window->windowState()) == Qt::WindowNoState) && withinFrameBorder);
+    return ((Utils::windowStatesToWindowState(window->windowState()) == Qt::WindowNoState) && withinFrameBorder);
 }
 
 void FramelessWidgetsHelperPrivate::setSystemButtonState(const SystemButtonType button, const ButtonState state)
@@ -817,42 +629,45 @@ void FramelessWidgetsHelperPrivate::setSystemButtonState(const SystemButtonType
     Q_UNUSED(state);
 }
 
-void FramelessWidgetsHelperPrivate::moveWindowToDesktopCenter()
+void FramelessWidgetsHelper::moveWindowToDesktopCenter()
 {
-    if (!m_window) {
+    Q_D(FramelessWidgetsHelper);
+    if (!d->window) {
         return;
     }
-    Utils::moveWindowToDesktopCenter(&getWindowData()->params, true);
+    Utils::moveWindowToDesktopCenter(&d->getWindowData()->params, true);
 }
 
-void FramelessWidgetsHelperPrivate::bringWindowToFront()
+void FramelessWidgetsHelper::bringWindowToFront()
 {
-    if (!m_window) {
+    Q_D(FramelessWidgetsHelper);
+    if (!d->window) {
         return;
     }
 #ifdef Q_OS_WINDOWS
-    std::ignore = Utils::bringWindowToFront(m_window->winId());
+    std::ignore = Utils::bringWindowToFront(d->window->winId());
 #else
-    if (m_window->isHidden()) {
-        m_window->show();
+    if (d->window->isHidden()) {
+        d->window->show();
     }
-    if (m_window->isMinimized()) {
-        m_window->setWindowState(m_window->windowState() & ~Qt::WindowMinimized);
+    if (d->window->isMinimized()) {
+        d->window->setWindowState(d->window->windowState() & ~Qt::WindowMinimized);
     }
-    m_window->raise();
-    m_window->activateWindow();
+    d->window->raise();
+    d->window->activateWindow();
 #endif
 }
 
-void FramelessWidgetsHelperPrivate::showSystemMenu(const QPoint &pos)
+void FramelessWidgetsHelper::showSystemMenu(const QPoint &pos)
 {
-    if (!m_window) {
+    Q_D(FramelessWidgetsHelper);
+    if (!d->window) {
         return;
     }
-    const WId windowId = m_window->winId();
-    const QPoint nativePos = Utils::toNativeGlobalPosition(m_window->windowHandle(), pos);
+    const WId windowId = d->window->winId();
+    const QPoint nativePos = Utils::toNativeGlobalPosition(d->window->windowHandle(), pos);
 #ifdef Q_OS_WINDOWS
-    std::ignore = Utils::showSystemMenu(windowId, nativePos, false, &getWindowData()->params);
+    std::ignore = Utils::showSystemMenu(windowId, nativePos, false, &d->getWindowData()->params);
 #elif defined(Q_OS_LINUX)
     Utils::openSystemMenu(windowId, nativePos);
 #else
@@ -861,33 +676,36 @@ void FramelessWidgetsHelperPrivate::showSystemMenu(const QPoint &pos)
 #endif
 }
 
-void FramelessWidgetsHelperPrivate::windowStartSystemMove2(const QPoint &pos)
+void FramelessWidgetsHelper::windowStartSystemMove2(const QPoint &pos)
 {
-    if (!m_window) {
+    Q_D(FramelessWidgetsHelper);
+    if (!d->window) {
         return;
     }
-    std::ignore = Utils::startSystemMove(m_window->windowHandle(), pos);
+    std::ignore = Utils::startSystemMove(d->window->windowHandle(), pos);
 }
 
-void FramelessWidgetsHelperPrivate::windowStartSystemResize2(const Qt::Edges edges, const QPoint &pos)
+void FramelessWidgetsHelper::windowStartSystemResize2(const Qt::Edges edges, const QPoint &pos)
 {
-    if (!m_window) {
+    Q_D(FramelessWidgetsHelper);
+    if (!d->window) {
         return;
     }
     if (edges == Qt::Edges{}) {
         return;
     }
-    std::ignore = Utils::startSystemResize(m_window->windowHandle(), edges, pos);
+    std::ignore = Utils::startSystemResize(d->window->windowHandle(), edges, pos);
 }
 
-void FramelessWidgetsHelperPrivate::setSystemButton(QWidget *widget, const SystemButtonType buttonType)
+void FramelessWidgetsHelper::setSystemButton(QWidget *widget, const SystemButtonType buttonType)
 {
     Q_ASSERT(widget);
     Q_ASSERT(buttonType != SystemButtonType::Unknown);
     if (!widget || (buttonType == SystemButtonType::Unknown)) {
         return;
     }
-    FramelessWidgetsHelperData *data = getWindowDataMutable();
+    Q_D(FramelessWidgetsHelper);
+    FramelessWidgetsHelperData *data = d->getWindowDataMutable();
     if (!data) {
         return;
     }
@@ -929,64 +747,125 @@ FramelessWidgetsHelper *FramelessWidgetsHelper::get(QObject *object)
     return FramelessWidgetsHelperPrivate::findOrCreateFramelessHelper(object);
 }
 
-QWidget *FramelessWidgetsHelper::titleBarWidget() const
+QWidget *FramelessWidgetsHelper::window() const
 {
     Q_D(const FramelessWidgetsHelper);
-    return d->getTitleBarWidget();
+    return d->window;
 }
 
-bool FramelessWidgetsHelper::isWindowFixedSize() const
+MicaMaterial *FramelessWidgetsHelper::micaMaterial() const
 {
     Q_D(const FramelessWidgetsHelper);
-    return d->isWindowFixedSize();
+    return d->getMicaMaterialIfAny();
 }
 
-bool FramelessWidgetsHelper::isBlurBehindWindowEnabled() const
+WindowBorderPainter *FramelessWidgetsHelper::windowBorder() const
 {
     Q_D(const FramelessWidgetsHelper);
-    return d->isBlurBehindWindowEnabled();
+    return d->getWindowBorderIfAny();
 }
 
-QWidget *FramelessWidgetsHelper::window() const
+bool FramelessWidgetsHelper::isWindowFixedSize() const
 {
     Q_D(const FramelessWidgetsHelper);
-    return d->window();
+    if (!d->window) {
+        return false;
+    }
+    return isWidgetFixedSize(d->window);
 }
 
-bool FramelessWidgetsHelper::isContentExtendedIntoTitleBar() const
+void FramelessWidgetsHelper::setWindowFixedSize(const bool value)
 {
-    Q_D(const FramelessWidgetsHelper);
-    return d->isContentExtendedIntoTitleBar();
+    Q_D(FramelessWidgetsHelper);
+    if (!d->window) {
+        return;
+    }
+    if (isWindowFixedSize() == value) {
+        return;
+    }
+    if (value) {
+        d->savedSizePolicy = d->window->sizePolicy();
+        d->window->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
+        d->window->setFixedSize(d->window->size());
+    } else {
+        d->window->setSizePolicy(d->savedSizePolicy);
+        d->window->setMinimumSize(kDefaultWindowSize);
+        d->window->setMaximumSize(QSize(QWIDGETSIZE_MAX, QWIDGETSIZE_MAX));
+    }
+#ifdef Q_OS_WINDOWS
+    std::ignore = Utils::setAeroSnappingEnabled(d->window->winId(), !value);
+#endif
+    d->emitSignalForAllInstances("windowFixedSizeChanged");
 }
 
-MicaMaterial *FramelessWidgetsHelper::micaMaterial() const
+bool FramelessWidgetsHelper::isBlurBehindWindowEnabled() const
 {
     Q_D(const FramelessWidgetsHelper);
-    return d->getMicaMaterialIfAny();
+    return d->blurBehindWindowEnabled;
 }
 
-WindowBorderPainter *FramelessWidgetsHelper::windowBorder() const
+void FramelessWidgetsHelper::setBlurBehindWindowEnabled(const bool enable)
 {
-    Q_D(const FramelessWidgetsHelper);
-    return d->getWindowBorderIfAny();
+    Q_D(FramelessWidgetsHelper);
+    if (!d->window) {
+        return;
+    }
+    if (d->blurBehindWindowEnabled == enable) {
+        return;
+    }
+    if (Utils::isBlurBehindWindowSupported()) {
+        QPalette palette = d->window->palette();
+        if (enable) {
+            d->savedWindowBackgroundColor = palette.color(QPalette::Window);
+        }
+        palette.setColor(QPalette::Window, (enable ? kDefaultTransparentColor : d->savedWindowBackgroundColor));
+        d->window->setPalette(palette);
+        if (Utils::setBlurBehindWindowEnabled(d->window->winId(), (enable ? BlurMode::Default : BlurMode::Disable), {})) {
+            d->blurBehindWindowEnabled = enable;
+            d->emitSignalForAllInstances("blurBehindWindowEnabledChanged");
+        } else {
+            WARNING << "Failed to enable/disable blur behind window.";
+        }
+    } else {
+        if (WidgetsSharedHelper * const helper = d->findOrCreateSharedHelper(d->window)) {
+            d->blurBehindWindowEnabled = enable;
+            helper->setMicaEnabled(d->blurBehindWindowEnabled);
+            d->emitSignalForAllInstances("blurBehindWindowEnabledChanged");
+        } else {
+            DEBUG << "Blur behind window is not supported on current platform.";
+        }
+    }
 }
 
 bool FramelessWidgetsHelper::isReady() const
 {
     Q_D(const FramelessWidgetsHelper);
-    return d->isReady();
+    return d->qpaReady;
 }
 
 void FramelessWidgetsHelper::waitForReady()
 {
     Q_D(FramelessWidgetsHelper);
-    d->waitForReady();
+    if (d->qpaReady) {
+        return;
+    }
+#if 1
+    QEventLoop loop{};
+    const QMetaObject::Connection connection = connect(this, &FramelessWidgetsHelper::ready, &loop, &QEventLoop::quit);
+    loop.exec();
+    disconnect(connection);
+#else
+    while (!d->qpaReady) {
+        QCoreApplication::processEvents();
+    }
+#endif
 }
 
-void FramelessWidgetsHelper::extendsContentIntoTitleBar(const bool value)
+bool FramelessWidgetsHelper::isContentExtendedIntoTitleBar() const
 {
-    Q_D(FramelessWidgetsHelper);
-    d->extendsContentIntoTitleBar(value);
+    Q_D(const FramelessWidgetsHelper);
+    const FramelessWidgetsHelperData *data = d->getWindowData();
+    return (data ? data->ready : false);
 }
 
 void FramelessWidgetsHelper::setTitleBarWidget(QWidget *widget)
@@ -996,18 +875,19 @@ void FramelessWidgetsHelper::setTitleBarWidget(QWidget *widget)
         return;
     }
     Q_D(FramelessWidgetsHelper);
-    d->setTitleBarWidget(widget);
+    FramelessWidgetsHelperData *data = d->getWindowDataMutable();
+    if (!data || (data->titleBarWidget == widget)) {
+        return;
+    }
+    data->titleBarWidget = widget;
+    d->emitSignalForAllInstances("titleBarWidgetChanged");
 }
 
-void FramelessWidgetsHelper::setSystemButton(QWidget *widget, const SystemButtonType buttonType)
+QWidget *FramelessWidgetsHelper::titleBarWidget() const
 {
-    Q_ASSERT(widget);
-    Q_ASSERT(buttonType != SystemButtonType::Unknown);
-    if (!widget || (buttonType == SystemButtonType::Unknown)) {
-        return;
-    }
-    Q_D(FramelessWidgetsHelper);
-    d->setSystemButton(widget, buttonType);
+    Q_D(const FramelessWidgetsHelper);
+    const FramelessWidgetsHelperData *data = d->getWindowData();
+    return (data ? data->titleBarWidget : nullptr);
 }
 
 void FramelessWidgetsHelper::setHitTestVisible(QWidget *widget, const bool visible)
@@ -1017,7 +897,15 @@ void FramelessWidgetsHelper::setHitTestVisible(QWidget *widget, const bool visib
         return;
     }
     Q_D(FramelessWidgetsHelper);
-    d->setHitTestVisible(widget, visible);
+    FramelessWidgetsHelperData *data = d->getWindowDataMutable();
+    if (!data) {
+        return;
+    }
+    if (visible) {
+        data->hitTestVisibleWidgets.append(widget);
+    } else {
+        data->hitTestVisibleWidgets.removeAll(widget);
+    }
 }
 
 void FramelessWidgetsHelper::setHitTestVisible(const QRect &rect, const bool visible)
@@ -1027,7 +915,15 @@ void FramelessWidgetsHelper::setHitTestVisible(const QRect &rect, const bool vis
         return;
     }
     Q_D(FramelessWidgetsHelper);
-    d->setHitTestVisible(rect, visible);
+    FramelessWidgetsHelperData *data = d->getWindowDataMutable();
+    if (!data) {
+        return;
+    }
+    if (visible) {
+        data->hitTestVisibleRects.append(rect);
+    } else {
+        data->hitTestVisibleRects.removeAll(rect);
+    }
 }
 
 void FramelessWidgetsHelper::setHitTestVisible(QObject *object, const bool visible)
@@ -1036,53 +932,26 @@ void FramelessWidgetsHelper::setHitTestVisible(QObject *object, const bool visib
     if (!object) {
         return;
     }
-    Q_D(FramelessWidgetsHelper);
-    d->setHitTestVisible(object, visible);
-}
-
-void FramelessWidgetsHelper::showSystemMenu(const QPoint &pos)
-{
-    Q_D(FramelessWidgetsHelper);
-    d->showSystemMenu(pos);
-}
-
-void FramelessWidgetsHelper::windowStartSystemMove2(const QPoint &pos)
-{
-    Q_D(FramelessWidgetsHelper);
-    d->windowStartSystemMove2(pos);
-}
-
-void FramelessWidgetsHelper::windowStartSystemResize2(const Qt::Edges edges, const QPoint &pos)
-{
-    if (edges == Qt::Edges{}) {
+    const auto widget = qobject_cast<QWidget *>(object);
+    Q_ASSERT(widget);
+    if (!widget) {
         return;
     }
-    Q_D(FramelessWidgetsHelper);
-    d->windowStartSystemResize2(edges, pos);
-}
-
-void FramelessWidgetsHelper::moveWindowToDesktopCenter()
-{
-    Q_D(FramelessWidgetsHelper);
-    d->moveWindowToDesktopCenter();
-}
-
-void FramelessWidgetsHelper::bringWindowToFront()
-{
-    Q_D(FramelessWidgetsHelper);
-    d->bringWindowToFront();
-}
-
-void FramelessWidgetsHelper::setWindowFixedSize(const bool value)
-{
-    Q_D(FramelessWidgetsHelper);
-    d->setWindowFixedSize(value);
+    setHitTestVisible(widget, visible);
 }
 
-void FramelessWidgetsHelper::setBlurBehindWindowEnabled(const bool value)
+void FramelessWidgetsHelper::extendsContentIntoTitleBar(const bool value)
 {
+    if (isContentExtendedIntoTitleBar() == value) {
+        return;
+    }
     Q_D(FramelessWidgetsHelper);
-    d->setBlurBehindWindowEnabled(value, {});
+    if (value) {
+        d->attach();
+    } else {
+        d->detach();
+    }
+    d->emitSignalForAllInstances("extendsContentIntoTitleBarChanged");
 }
 
 FRAMELESSHELPER_END_NAMESPACE
diff --git a/src/widgets/standardsystembutton.cpp b/src/widgets/standardsystembutton.cpp
index 95e0141d..a7d4991f 100644
--- a/src/widgets/standardsystembutton.cpp
+++ b/src/widgets/standardsystembutton.cpp
@@ -56,7 +56,6 @@ StandardSystemButtonPrivate::StandardSystemButtonPrivate(StandardSystemButton *q
         return;
     }
     q_ptr = q;
-    initialize();
 }
 
 StandardSystemButtonPrivate::~StandardSystemButtonPrivate() = default;
@@ -79,173 +78,206 @@ const StandardSystemButtonPrivate *StandardSystemButtonPrivate::get(const Standa
     return pub->d_func();
 }
 
-QString StandardSystemButtonPrivate::getGlyph() const
+QSize StandardSystemButtonPrivate::getRecommendedButtonSize()
 {
-    return m_glyph;
+    return kDefaultSystemButtonSize;
+}
+
+StandardSystemButton::StandardSystemButton(QWidget *parent)
+    : QPushButton(parent), d_ptr(new StandardSystemButtonPrivate(this))
+{
+    FramelessManagerPrivate::initializeIconFont();
+    setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
+    setFixedSize(StandardSystemButtonPrivate::getRecommendedButtonSize());
+    setIconSize(kDefaultSystemButtonIconSize);
+    setMouseTracking(true);
+    setAttribute(Qt::WA_Hover);
+}
+
+StandardSystemButton::StandardSystemButton(const SystemButtonType type, QWidget *parent)
+    : StandardSystemButton(parent)
+{
+    setButtonType(type);
+}
+
+StandardSystemButton::~StandardSystemButton() = default;
+
+QSize StandardSystemButton::sizeHint() const
+{
+    return StandardSystemButtonPrivate::getRecommendedButtonSize();
+}
+
+QString StandardSystemButton::glyph() const
+{
+    Q_D(const StandardSystemButton);
+    return d->glyph;
 }
 
-void StandardSystemButtonPrivate::setGlyph(const QString &value)
+void StandardSystemButton::setGlyph(const QString &value)
 {
     Q_ASSERT(!value.isEmpty());
     if (value.isEmpty()) {
         return;
     }
-    if (m_glyph == value) {
+    Q_D(StandardSystemButton);
+    if (d->glyph == value) {
         return;
     }
-    m_glyph = value;
-    Q_Q(StandardSystemButton);
-    q->update();
-    Q_EMIT q->glyphChanged();
+    d->glyph = value;
+    update();
+    Q_EMIT glyphChanged();
 }
 
-SystemButtonType StandardSystemButtonPrivate::getButtonType() const
+SystemButtonType StandardSystemButton::buttonType() const
 {
-    return m_buttonType;
+    Q_D(const StandardSystemButton);
+    return d->buttonType;
 }
 
-void StandardSystemButtonPrivate::setButtonType(const SystemButtonType type)
+void StandardSystemButton::setButtonType(const SystemButtonType type)
 {
     Q_ASSERT(type != SystemButtonType::Unknown);
     if (type == SystemButtonType::Unknown) {
         return;
     }
-    if (m_buttonType == type) {
+    Q_D(StandardSystemButton);
+    if (d->buttonType == type) {
         return;
     }
-    m_buttonType = type;
-    setGlyph(Utils::getSystemButtonGlyph(m_buttonType));
-    Q_Q(StandardSystemButton);
-    q->update();
+    d->buttonType = type;
+    setGlyph(Utils::getSystemButtonGlyph(d->buttonType));
+    update();
 }
 
-QSize StandardSystemButtonPrivate::getRecommendedButtonSize() const
-{
-    return kDefaultSystemButtonSize;
-}
-
-QColor StandardSystemButtonPrivate::getHoverColor() const
+QColor StandardSystemButton::hoverColor() const
 {
-    return m_hoverColor;
+    Q_D(const StandardSystemButton);
+    return d->hoverColor;
 }
 
-QColor StandardSystemButtonPrivate::getPressColor() const
+QColor StandardSystemButton::pressColor() const
 {
-    return m_pressColor;
+    Q_D(const StandardSystemButton);
+    return d->pressColor;
 }
 
-QColor StandardSystemButtonPrivate::getNormalColor() const
+QColor StandardSystemButton::normalColor() const
 {
-    return m_normalColor;
+    Q_D(const StandardSystemButton);
+    return d->normalColor;
 }
 
-QColor StandardSystemButtonPrivate::getActiveForegroundColor() const
+QColor StandardSystemButton::activeForegroundColor() const
 {
-    return m_activeForegroundColor;
+    Q_D(const StandardSystemButton);
+    return d->activeForegroundColor;
 }
 
-QColor StandardSystemButtonPrivate::getInactiveForegroundColor() const
+QColor StandardSystemButton::inactiveForegroundColor() const
 {
-    return m_inactiveForegroundColor;
+    Q_D(const StandardSystemButton);
+    return d->inactiveForegroundColor;
 }
 
-bool StandardSystemButtonPrivate::isActive() const
+bool StandardSystemButton::isActive() const
 {
-    return m_active;
+    Q_D(const StandardSystemButton);
+    return d->active;
 }
 
-int StandardSystemButtonPrivate::glyphSize() const
+int StandardSystemButton::glyphSize() const
 {
-    return m_glyphSize.value_or(FramelessManagerPrivate::getIconFont().pointSize());
+    Q_D(const StandardSystemButton);
+    return d->glyphSize.value_or(FramelessManagerPrivate::getIconFont().pointSize());
 }
 
-void StandardSystemButtonPrivate::setHoverColor(const QColor &value)
+void StandardSystemButton::setHoverColor(const QColor &value)
 {
     Q_ASSERT(value.isValid());
     if (!value.isValid()) {
         return;
     }
-    if (m_hoverColor == value) {
+    Q_D(StandardSystemButton);
+    if (d->hoverColor == value) {
         return;
     }
-    m_hoverColor = value;
-    Q_Q(StandardSystemButton);
-    q->update();
-    Q_EMIT q->hoverColorChanged();
+    d->hoverColor = value;
+    update();
+    Q_EMIT hoverColorChanged();
 }
 
-void StandardSystemButtonPrivate::setPressColor(const QColor &value)
+void StandardSystemButton::setPressColor(const QColor &value)
 {
     Q_ASSERT(value.isValid());
     if (!value.isValid()) {
         return;
     }
-    if (m_pressColor == value) {
+    Q_D(StandardSystemButton);
+    if (d->pressColor == value) {
         return;
     }
-    m_pressColor = value;
-    Q_Q(StandardSystemButton);
-    q->update();
-    Q_EMIT q->pressColorChanged();
+    d->pressColor = value;
+    update();
+    Q_EMIT pressColorChanged();
 }
 
-void StandardSystemButtonPrivate::setNormalColor(const QColor &value)
+void StandardSystemButton::setNormalColor(const QColor &value)
 {
     Q_ASSERT(value.isValid());
     if (!value.isValid()) {
         return;
     }
-    if (m_normalColor == value) {
+    Q_D(StandardSystemButton);
+    if (d->normalColor == value) {
         return;
     }
-    m_normalColor = value;
-    Q_Q(StandardSystemButton);
-    q->update();
-    Q_EMIT q->normalColorChanged();
+    d->normalColor = value;
+    update();
+    Q_EMIT normalColorChanged();
 }
 
-void StandardSystemButtonPrivate::setActiveForegroundColor(const QColor &value)
+void StandardSystemButton::setActiveForegroundColor(const QColor &value)
 {
     Q_ASSERT(value.isValid());
     if (!value.isValid()) {
         return;
     }
-    if (m_activeForegroundColor == value) {
+    Q_D(StandardSystemButton);
+    if (d->activeForegroundColor == value) {
         return;
     }
-    m_activeForegroundColor = value;
-    Q_Q(StandardSystemButton);
-    q->update();
-    Q_EMIT q->activeForegroundColorChanged();
+    d->activeForegroundColor = value;
+    update();
+    Q_EMIT activeForegroundColorChanged();
 }
 
-void StandardSystemButtonPrivate::setInactiveForegroundColor(const QColor &value)
+void StandardSystemButton::setInactiveForegroundColor(const QColor &value)
 {
     Q_ASSERT(value.isValid());
     if (!value.isValid()) {
         return;
     }
-    if (m_inactiveForegroundColor == value) {
+    Q_D(StandardSystemButton);
+    if (d->inactiveForegroundColor == value) {
         return;
     }
-    m_inactiveForegroundColor = value;
-    Q_Q(StandardSystemButton);
-    q->update();
-    Q_EMIT q->inactiveForegroundColorChanged();
+    d->inactiveForegroundColor = value;
+    update();
+    Q_EMIT inactiveForegroundColorChanged();
 }
 
-void StandardSystemButtonPrivate::setActive(const bool value)
+void StandardSystemButton::setActive(const bool value)
 {
-    if (m_active == value) {
+    Q_D(StandardSystemButton);
+    if (d->active == value) {
         return;
     }
-    m_active = value;
-    Q_Q(StandardSystemButton);
-    q->update();
-    Q_EMIT q->activeChanged();
+    d->active = value;
+    update();
+    Q_EMIT activeChanged();
 }
 
-void StandardSystemButtonPrivate::setGlyphSize(const int value)
+void StandardSystemButton::setGlyphSize(const int value)
 {
     Q_ASSERT(value > 0);
     if (value <= 0) {
@@ -254,205 +286,61 @@ void StandardSystemButtonPrivate::setGlyphSize(const int value)
     if (glyphSize() == value) {
         return;
     }
-    m_glyphSize = value;
-    Q_Q(StandardSystemButton);
-    q->update();
-    Q_EMIT q->glyphSizeChanged();
+    Q_D(StandardSystemButton);
+    d->glyphSize = value;
+    update();
+    Q_EMIT glyphSizeChanged();
 }
 
-void StandardSystemButtonPrivate::paintEventHandler(QPaintEvent *event)
+void StandardSystemButton::paintEvent(QPaintEvent *event)
 {
     Q_ASSERT(event);
     if (!event) {
         return;
     }
-    Q_Q(StandardSystemButton);
-    QPainter painter(q);
+    Q_D(StandardSystemButton);
+    QPainter painter(this);
     painter.save();
     painter.setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing
                            | QPainter::SmoothPixmapTransform);
-    const auto backgroundColor = [this, q]() -> QColor {
+    const auto backgroundColor = [this, d]() -> QColor {
         // The pressed state has higher priority than the hovered state.
-        if (q->isDown() && m_pressColor.isValid()) {
-            return m_pressColor;
+        if (isDown() && d->pressColor.isValid()) {
+            return d->pressColor;
         }
-        if (q->underMouse() && m_hoverColor.isValid()) {
-            return m_hoverColor;
+        if (underMouse() && d->hoverColor.isValid()) {
+            return d->hoverColor;
         }
-        if (m_normalColor.isValid()) {
-            return m_normalColor;
+        if (d->normalColor.isValid()) {
+            return d->normalColor;
         }
         return {};
     }();
-    const QRect buttonRect = {QPoint(0, 0), q->size()};
+    const QRect buttonRect = {QPoint(0, 0), size()};
     if (backgroundColor.isValid()) {
         painter.fillRect(buttonRect, backgroundColor);
     }
-    if (!m_glyph.isEmpty()) {
-        painter.setPen([this, q]() -> QColor {
-            if (!q->underMouse() && !m_active && m_inactiveForegroundColor.isValid()) {
-                return m_inactiveForegroundColor;
+    if (!d->glyph.isEmpty()) {
+        painter.setPen([this, d]() -> QColor {
+            if (!underMouse() && !d->active && d->inactiveForegroundColor.isValid()) {
+                return d->inactiveForegroundColor;
             }
-            if (m_activeForegroundColor.isValid()) {
-                return m_activeForegroundColor;
+            if (d->activeForegroundColor.isValid()) {
+                return d->activeForegroundColor;
             }
             return kDefaultBlackColor;
         }());
-        painter.setFont([this]() -> QFont {
+        painter.setFont([d]() -> QFont {
             QFont font = FramelessManagerPrivate::getIconFont();
-            if (m_glyphSize.has_value()) {
-                font.setPointSize(m_glyphSize.value());
+            if (d->glyphSize.has_value()) {
+                font.setPointSize(d->glyphSize.value());
             }
             return font;
         }());
-        painter.drawText(buttonRect, Qt::AlignCenter, m_glyph);
+        painter.drawText(buttonRect, Qt::AlignCenter, d->glyph);
     }
     painter.restore();
     event->accept();
 }
 
-void StandardSystemButtonPrivate::initialize()
-{
-    FramelessManagerPrivate::initializeIconFont();
-    Q_Q(StandardSystemButton);
-    q->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
-    q->setFixedSize(getRecommendedButtonSize());
-    q->setIconSize(kDefaultSystemButtonIconSize);
-    q->setMouseTracking(true);
-    q->setAttribute(Qt::WA_Hover);
-}
-
-StandardSystemButton::StandardSystemButton(QWidget *parent)
-    : QPushButton(parent), d_ptr(new StandardSystemButtonPrivate(this))
-{
-}
-
-StandardSystemButton::StandardSystemButton(const SystemButtonType type, QWidget *parent)
-    : StandardSystemButton(parent)
-{
-    setButtonType(type);
-}
-
-StandardSystemButton::~StandardSystemButton() = default;
-
-QSize StandardSystemButton::sizeHint() const
-{
-    Q_D(const StandardSystemButton);
-    return d->getRecommendedButtonSize();
-}
-
-SystemButtonType StandardSystemButton::buttonType()
-{
-    Q_D(const StandardSystemButton);
-    return d->getButtonType();
-}
-
-QString StandardSystemButton::glyph() const
-{
-    Q_D(const StandardSystemButton);
-    return d->getGlyph();
-}
-
-void StandardSystemButton::setButtonType(const SystemButtonType value)
-{
-    Q_D(StandardSystemButton);
-    d->setButtonType(value);
-}
-
-void StandardSystemButton::setGlyph(const QString &glyph)
-{
-    Q_D(StandardSystemButton);
-    d->setGlyph(glyph);
-}
-
-QColor StandardSystemButton::hoverColor() const
-{
-    Q_D(const StandardSystemButton);
-    return d->getHoverColor();
-}
-
-void StandardSystemButton::setHoverColor(const QColor &value)
-{
-    Q_D(StandardSystemButton);
-    d->setHoverColor(value);
-}
-
-QColor StandardSystemButton::pressColor() const
-{
-    Q_D(const StandardSystemButton);
-    return d->getPressColor();
-}
-
-QColor StandardSystemButton::normalColor() const
-{
-    Q_D(const StandardSystemButton);
-    return d->getNormalColor();
-}
-
-QColor StandardSystemButton::activeForegroundColor() const
-{
-    Q_D(const StandardSystemButton);
-    return d->getActiveForegroundColor();
-}
-
-QColor StandardSystemButton::inactiveForegroundColor() const
-{
-    Q_D(const StandardSystemButton);
-    return d->getInactiveForegroundColor();
-}
-
-bool StandardSystemButton::isActive() const
-{
-    Q_D(const StandardSystemButton);
-    return d->isActive();
-}
-
-int StandardSystemButton::glyphSize() const
-{
-    Q_D(const StandardSystemButton);
-    return d->glyphSize();
-}
-
-void StandardSystemButton::setPressColor(const QColor &value)
-{
-    Q_D(StandardSystemButton);
-    d->setPressColor(value);
-}
-
-void StandardSystemButton::setNormalColor(const QColor &value)
-{
-    Q_D(StandardSystemButton);
-    d->setNormalColor(value);
-}
-
-void StandardSystemButton::setActiveForegroundColor(const QColor &value)
-{
-    Q_D(StandardSystemButton);
-    d->setActiveForegroundColor(value);
-}
-
-void StandardSystemButton::setInactiveForegroundColor(const QColor &value)
-{
-    Q_D(StandardSystemButton);
-    d->setInactiveForegroundColor(value);
-}
-
-void StandardSystemButton::setActive(const bool value)
-{
-    Q_D(StandardSystemButton);
-    d->setActive(value);
-}
-
-void StandardSystemButton::setGlyphSize(const int value)
-{
-    Q_D(StandardSystemButton);
-    d->setGlyphSize(value);
-}
-
-void StandardSystemButton::paintEvent(QPaintEvent *event)
-{
-    Q_D(StandardSystemButton);
-    d->paintEventHandler(event);
-}
-
 FRAMELESSHELPER_END_NAMESPACE
diff --git a/src/widgets/standardtitlebar.cpp b/src/widgets/standardtitlebar.cpp
index 17222def..e11c75aa 100644
--- a/src/widgets/standardtitlebar.cpp
+++ b/src/widgets/standardtitlebar.cpp
@@ -83,58 +83,6 @@ const StandardTitleBarPrivate *StandardTitleBarPrivate::get(const StandardTitleB
     return pub->d_func();
 }
 
-Qt::Alignment StandardTitleBarPrivate::titleLabelAlignment() const
-{
-    return m_labelAlignment;
-}
-
-void StandardTitleBarPrivate::setTitleLabelAlignment(const Qt::Alignment value)
-{
-    if (m_labelAlignment == value) {
-        return;
-    }
-    m_labelAlignment = value;
-    Q_Q(StandardTitleBar);
-    q->update();
-    Q_EMIT q->titleLabelAlignmentChanged();
-}
-
-bool StandardTitleBarPrivate::isExtended() const
-{
-    return m_extended;
-}
-
-void StandardTitleBarPrivate::setExtended(const bool value)
-{
-    if (m_extended == value) {
-        return;
-    }
-    m_extended = value;
-    Q_Q(StandardTitleBar);
-    q->setFixedHeight(m_extended ? kDefaultExtendedTitleBarHeight : kDefaultTitleBarHeight);
-    Q_EMIT q->extendedChanged();
-}
-
-bool StandardTitleBarPrivate::isHideWhenClose() const
-{
-    return m_hideWhenClose;
-}
-
-void StandardTitleBarPrivate::setHideWhenClose(const bool value)
-{
-    if (m_hideWhenClose == value) {
-        return;
-    }
-    m_hideWhenClose = value;
-    Q_Q(StandardTitleBar);
-    Q_EMIT q->hideWhenCloseChanged();
-}
-
-ChromePalette *StandardTitleBarPrivate::chromePalette() const
-{
-    return m_chromePalette;
-}
-
 QFont StandardTitleBarPrivate::defaultFont() const
 {
     Q_Q(const StandardTitleBar);
@@ -145,14 +93,14 @@ QFont StandardTitleBarPrivate::defaultFont() const
 
 StandardTitleBarPrivate::FontMetrics StandardTitleBarPrivate::titleLabelSize() const
 {
-    if (!m_window) {
+    if (!window) {
         return {};
     }
-    const QString text = m_window->windowTitle();
+    const QString text = window->windowTitle();
     if (text.isEmpty()) {
         return {};
     }
-    const QFont font = m_titleFont.value_or(defaultFont());
+    const QFont font = titleFont.value_or(defaultFont());
     const QFontMetrics fontMetrics(font);
     return {
         /* .width */ Utils::horizontalAdvance(fontMetrics, text),
@@ -161,143 +109,6 @@ StandardTitleBarPrivate::FontMetrics StandardTitleBarPrivate::titleLabelSize() c
     };
 }
 
-void StandardTitleBarPrivate::paintTitleBar(QPaintEvent *event)
-{
-    Q_ASSERT(event);
-    if (!event) {
-        return;
-    }
-    Q_Q(StandardTitleBar);
-    if (!m_window || !m_chromePalette) {
-        return;
-    }
-    const bool active = m_window->isActiveWindow();
-    const QColor backgroundColor = (active ?
-        m_chromePalette->titleBarActiveBackgroundColor() :
-        m_chromePalette->titleBarInactiveBackgroundColor());
-    const QColor foregroundColor = (active ?
-        m_chromePalette->titleBarActiveForegroundColor() :
-        m_chromePalette->titleBarInactiveForegroundColor());
-    QPainter painter(q);
-    painter.save();
-    painter.setRenderHints(QPainter::Antialiasing |
-        QPainter::TextAntialiasing | QPainter::SmoothPixmapTransform);
-    painter.fillRect(QRect(QPoint(0, 0), q->size()), backgroundColor);
-    if (m_titleLabelVisible) {
-        const QString text = m_window->windowTitle();
-        if (!text.isEmpty()) {
-            painter.setPen(foregroundColor);
-            painter.setFont(m_titleFont.value_or(defaultFont()));
-            const auto pos = [this, q]() -> QPoint {
-                const FontMetrics labelSize = titleLabelSize();
-                const int titleBarWidth = q->width();
-                int x = 0;
-                if (m_labelAlignment & Qt::AlignLeft) {
-                    x = (windowIconRect().right() + kDefaultTitleBarContentsMargin);
-                } else if (m_labelAlignment & Qt::AlignRight) {
-                    x = (titleBarWidth - kDefaultTitleBarContentsMargin - labelSize.width);
-#ifndef Q_OS_MACOS
-                    x -= (titleBarWidth - m_minimizeButton->x());
-#endif // Q_OS_MACOS
-                } else if (m_labelAlignment & Qt::AlignHCenter) {
-                    x = std::round(qreal(titleBarWidth - labelSize.width) / qreal(2));
-                } else {
-                    WARNING << "The alignment for the title label is not set!";
-                }
-                const int y = std::round((qreal(q->height() - labelSize.height) / qreal(2)) + qreal(labelSize.ascent));
-                return {x, y};
-            }();
-            painter.drawText(pos, text);
-        }
-    }
-    if (m_windowIconVisible) {
-        const QIcon icon = m_window->windowIcon();
-        if (!icon.isNull()) {
-            icon.paint(&painter, windowIconRect());
-        }
-    }
-    painter.restore();
-    event->accept();
-}
-
-bool StandardTitleBarPrivate::titleLabelVisible() const
-{
-    return m_titleLabelVisible;
-}
-
-void StandardTitleBarPrivate::setTitleLabelVisible(const bool value)
-{
-    if (m_titleLabelVisible == value) {
-        return;
-    }
-    m_titleLabelVisible = value;
-    Q_Q(StandardTitleBar);
-    q->update();
-    Q_EMIT q->titleLabelVisibleChanged();
-}
-
-QSize StandardTitleBarPrivate::windowIconSize() const
-{
-    return m_windowIconSize.value_or(kDefaultWindowIconSize);
-}
-
-void StandardTitleBarPrivate::setWindowIconSize(const QSize &value)
-{
-    Q_ASSERT(!value.isEmpty());
-    if (value.isEmpty()) {
-        return;
-    }
-    if (windowIconSize() == value) {
-        return;
-    }
-    m_windowIconSize = value;
-    Q_Q(StandardTitleBar);
-    q->update();
-    Q_EMIT q->windowIconSizeChanged();
-}
-
-bool StandardTitleBarPrivate::windowIconVisible() const
-{
-    return m_windowIconVisible;
-}
-
-void StandardTitleBarPrivate::setWindowIconVisible(const bool value)
-{
-    if (m_windowIconVisible == value) {
-        return;
-    }
-    m_windowIconVisible = value;
-    Q_Q(StandardTitleBar);
-    q->update();
-    Q_EMIT q->windowIconVisibleChanged();
-#ifndef Q_OS_MACOS
-    // Ideally we should use FramelessWidgetsHelper::get(this) everywhere, but sadly when
-    // we call it here, it may be too early that FramelessWidgetsHelper has not attached
-    // to the top level widget yet, and thus it will trigger an assert error (the assert
-    // should not be suppressed, because it usually indicates there's something really
-    // wrong). So here we have to use the top level widget directly, as a special case.
-    // NOTE: In your own code, you should always use FramelessWidgetsHelper::get(this)
-    // if possible.
-    FramelessWidgetsHelper::get(m_window)->setHitTestVisible(windowIconRect(), windowIconVisible_real());
-#endif // Q_OS_MACOS
-}
-
-QFont StandardTitleBarPrivate::titleFont() const
-{
-    return m_titleFont.value_or(QFont());
-}
-
-void StandardTitleBarPrivate::setTitleFont(const QFont &value)
-{
-    if (titleFont() == value) {
-        return;
-    }
-    m_titleFont = value;
-    Q_Q(StandardTitleBar);
-    q->update();
-    Q_EMIT q->titleFontChanged();
-}
-
 bool StandardTitleBarPrivate::mouseEventHandler(QMouseEvent *event)
 {
 #ifdef Q_OS_MACOS
@@ -319,7 +130,7 @@ bool StandardTitleBarPrivate::mouseEventHandler(QMouseEvent *event)
     switch (event->type()) {
     case QEvent::MouseButtonRelease:
         // We need a valid top level widget here.
-        if (m_window && interestArea) {
+        if (window && interestArea) {
             // Sadly the mouse release events are always triggered before the
             // mouse double click events, and if we intercept the mouse release
             // events here, we'll never get the double click events afterwards,
@@ -339,16 +150,16 @@ bool StandardTitleBarPrivate::mouseEventHandler(QMouseEvent *event)
                 // The close event is already triggered, don't try to show the
                 // system menu anymore, otherwise it will prevent our window
                 // from closing.
-                if (m_closeTriggered) {
+                if (closeTriggered) {
                     return;
                 }
                 // Please refer to the comments in StandardTitleBarPrivate::setWindowIconVisible().
-                FramelessWidgetsHelper::get(m_window)->showSystemMenu([button, q, &scenePos, this]() -> QPoint {
+                FramelessWidgetsHelper::get(window)->showSystemMenu([button, q, &scenePos, this]() -> QPoint {
                     QPoint pos = scenePos;
                     if (button == Qt::LeftButton) {
                         pos = {0, q->height()};
                     }
-                    return m_window->mapToGlobal(pos);
+                    return window->mapToGlobal(pos);
                 }());
             });
             // Don't eat this event, we have not handled it yet.
@@ -356,9 +167,9 @@ bool StandardTitleBarPrivate::mouseEventHandler(QMouseEvent *event)
         break;
     case QEvent::MouseButtonDblClick:
         // We need a valid top level widget here.
-        if (m_window && (button == Qt::LeftButton) && interestArea) {
-            m_closeTriggered = true;
-            m_window->close();
+        if (window && (button == Qt::LeftButton) && interestArea) {
+            closeTriggered = true;
+            window->close();
             // Eat this event, we have handled it here.
             event->accept();
             return true;
@@ -377,21 +188,21 @@ QRect StandardTitleBarPrivate::windowIconRect() const
     if (!windowIconVisible_real()) {
         return {};
     }
-    const QSize size = windowIconSize();
+    const QSize size = q->windowIconSize();
 #ifdef Q_OS_MACOS
     const auto x = [this, q, &size]() -> int {
-        if (m_labelAlignment & Qt::AlignLeft) {
+        if (labelAlignment & Qt::AlignLeft) {
             return (kMacOSChromeButtonAreaWidth + kDefaultTitleBarContentsMargin);
         }
         const int titleBarWidth = q->width();
         const int labelWidth = titleLabelSize().width;
-        if (m_labelAlignment & Qt::AlignRight) {
+        if (labelAlignment & Qt::AlignRight) {
             // We need two spacer here, one is on the right edge of the title bar,
             // the other one is between the window icon and the window label.
             return (titleBarWidth - kDefaultTitleBarContentsMargin
                     - labelWidth - kDefaultTitleBarContentsMargin - size.width());
         }
-        if (m_labelAlignment & Qt::AlignHCenter) {
+        if (labelAlignment & Qt::AlignHCenter) {
             const int centeredX = std::round(qreal(titleBarWidth - labelWidth) / qreal(2));
             return (centeredX - kDefaultTitleBarContentsMargin - size.width());
         }
@@ -407,7 +218,7 @@ QRect StandardTitleBarPrivate::windowIconRect() const
 
 bool StandardTitleBarPrivate::windowIconVisible_real() const
 {
-    return (m_windowIconVisible && !m_window->windowIcon().isNull());
+    return (windowIconVisible && !window->windowIcon().isNull());
 }
 
 bool StandardTitleBarPrivate::isInTitleBarIconArea(const QPoint &pos) const
@@ -421,9 +232,9 @@ bool StandardTitleBarPrivate::isInTitleBarIconArea(const QPoint &pos) const
 void StandardTitleBarPrivate::updateMaximizeButton()
 {
 #ifndef Q_OS_MACOS
-    const bool max = m_window->isMaximized();
-    m_maximizeButton->setButtonType(max ? SystemButtonType::Restore : SystemButtonType::Maximize);
-    m_maximizeButton->setToolTip(max ? tr("Restore") : tr("Maximize"));
+    const bool max = window->isMaximized();
+    maximizeButton->setButtonType(max ? SystemButtonType::Restore : SystemButtonType::Maximize);
+    maximizeButton->setToolTip(max ? tr("Restore") : tr("Maximize"));
 #endif // Q_OS_MACOS
 }
 
@@ -436,39 +247,39 @@ void StandardTitleBarPrivate::updateTitleBarColor()
 void StandardTitleBarPrivate::updateChromeButtonColor()
 {
 #ifndef Q_OS_MACOS
-    const bool active = m_window->isActiveWindow();
-    const QColor activeForeground = m_chromePalette->titleBarActiveForegroundColor();
-    const QColor inactiveForeground = m_chromePalette->titleBarInactiveForegroundColor();
-    const QColor normal = m_chromePalette->chromeButtonNormalColor();
-    const QColor hover = m_chromePalette->chromeButtonHoverColor();
-    const QColor press = m_chromePalette->chromeButtonPressColor();
-    m_minimizeButton->setActiveForegroundColor(activeForeground);
-    m_minimizeButton->setInactiveForegroundColor(inactiveForeground);
-    m_minimizeButton->setNormalColor(normal);
-    m_minimizeButton->setHoverColor(hover);
-    m_minimizeButton->setPressColor(press);
-    m_minimizeButton->setActive(active);
-    m_maximizeButton->setActiveForegroundColor(activeForeground);
-    m_maximizeButton->setInactiveForegroundColor(inactiveForeground);
-    m_maximizeButton->setNormalColor(normal);
-    m_maximizeButton->setHoverColor(hover);
-    m_maximizeButton->setPressColor(press);
-    m_maximizeButton->setActive(active);
-    m_closeButton->setActiveForegroundColor(activeForeground);
-    m_closeButton->setInactiveForegroundColor(inactiveForeground);
-    m_closeButton->setNormalColor(m_chromePalette->closeButtonNormalColor());
-    m_closeButton->setHoverColor(m_chromePalette->closeButtonHoverColor());
-    m_closeButton->setPressColor(m_chromePalette->closeButtonPressColor());
-    m_closeButton->setActive(active);
+    const bool active = window->isActiveWindow();
+    const QColor activeForeground = chromePalette->titleBarActiveForegroundColor();
+    const QColor inactiveForeground = chromePalette->titleBarInactiveForegroundColor();
+    const QColor normal = chromePalette->chromeButtonNormalColor();
+    const QColor hover = chromePalette->chromeButtonHoverColor();
+    const QColor press = chromePalette->chromeButtonPressColor();
+    minimizeButton->setActiveForegroundColor(activeForeground);
+    minimizeButton->setInactiveForegroundColor(inactiveForeground);
+    minimizeButton->setNormalColor(normal);
+    minimizeButton->setHoverColor(hover);
+    minimizeButton->setPressColor(press);
+    minimizeButton->setActive(active);
+    maximizeButton->setActiveForegroundColor(activeForeground);
+    maximizeButton->setInactiveForegroundColor(inactiveForeground);
+    maximizeButton->setNormalColor(normal);
+    maximizeButton->setHoverColor(hover);
+    maximizeButton->setPressColor(press);
+    maximizeButton->setActive(active);
+    closeButton->setActiveForegroundColor(activeForeground);
+    closeButton->setInactiveForegroundColor(inactiveForeground);
+    closeButton->setNormalColor(chromePalette->closeButtonNormalColor());
+    closeButton->setHoverColor(chromePalette->closeButtonHoverColor());
+    closeButton->setPressColor(chromePalette->closeButtonPressColor());
+    closeButton->setActive(active);
 #endif // Q_OS_MACOS
 }
 
 void StandardTitleBarPrivate::retranslateUi()
 {
 #ifndef Q_OS_MACOS
-    m_minimizeButton->setToolTip(tr("Minimize"));
-    m_maximizeButton->setToolTip(m_window->isMaximized() ? tr("Restore") : tr("Maximize"));
-    m_closeButton->setToolTip(tr("Close"));
+    minimizeButton->setToolTip(tr("Minimize"));
+    maximizeButton->setToolTip(window->isMaximized() ? tr("Restore") : tr("Maximize"));
+    closeButton->setToolTip(tr("Close"));
 #endif // Q_OS_MACOS
 }
 
@@ -483,17 +294,17 @@ bool StandardTitleBarPrivate::eventFilter(QObject *object, QEvent *event)
         return QObject::eventFilter(object, event);
     }
     const auto widget = qobject_cast<QWidget *>(object);
-    if (!widget->isWindow() || (widget != m_window)) {
+    if (!widget->isWindow() || (widget != window)) {
         return QObject::eventFilter(object, event);
     }
     switch (event->type()) {
     case QEvent::WindowStateChange:
         updateMaximizeButton();
         break;
-    case QEvent::ActivationChange:
+    case QEvent::ActivationChange: {
         updateTitleBarColor();
         updateChromeButtonColor();
-        break;
+    } break;
     case QEvent::LanguageChange:
         retranslateUi();
         break;
@@ -506,19 +317,19 @@ bool StandardTitleBarPrivate::eventFilter(QObject *object, QEvent *event)
 void StandardTitleBarPrivate::initialize()
 {
     Q_Q(StandardTitleBar);
-    m_window = q->window();
-    m_chromePalette = new ChromePalette(this);
-    connect(m_chromePalette, &ChromePalette::titleBarColorChanged,
+    window = q->window();
+    chromePalette = new ChromePalette(this);
+    connect(chromePalette, &ChromePalette::titleBarColorChanged,
         this, &StandardTitleBarPrivate::updateTitleBarColor);
-    connect(m_chromePalette, &ChromePalette::chromeButtonColorChanged,
+    connect(chromePalette, &ChromePalette::chromeButtonColorChanged,
         this, &StandardTitleBarPrivate::updateChromeButtonColor);
     q->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed);
     q->setFixedHeight(kDefaultTitleBarHeight);
-    connect(m_window, &QWidget::windowIconChanged, this, [q](const QIcon &icon){
+    connect(window, &QWidget::windowIconChanged, this, [q](const QIcon &icon){
         Q_UNUSED(icon);
         q->update();
     });
-    connect(m_window, &QWidget::windowTitleChanged, this, [q](const QString &title){
+    connect(window, &QWidget::windowTitleChanged, this, [q](const QString &title){
         Q_UNUSED(title);
         q->update();
     });
@@ -526,26 +337,25 @@ void StandardTitleBarPrivate::initialize()
     const auto titleBarLayout = new QHBoxLayout(q);
     titleBarLayout->setSpacing(0);
     titleBarLayout->setContentsMargins(0, 0, 0, 0);
-    q->setLayout(titleBarLayout);
-    setTitleLabelAlignment(Qt::AlignCenter);
+    q->setTitleLabelAlignment(Qt::AlignCenter);
 #else // !Q_OS_MACOS
-    m_minimizeButton = new StandardSystemButton(SystemButtonType::Minimize, q);
-    connect(m_minimizeButton, &StandardSystemButton::clicked, m_window, &QWidget::showMinimized);
-    m_maximizeButton = new StandardSystemButton(SystemButtonType::Maximize, q);
+    minimizeButton = new StandardSystemButton(SystemButtonType::Minimize, q);
+    connect(minimizeButton, &StandardSystemButton::clicked, window, &QWidget::showMinimized);
+    maximizeButton = new StandardSystemButton(SystemButtonType::Maximize, q);
     updateMaximizeButton();
-    connect(m_maximizeButton, &StandardSystemButton::clicked, this, [this](){
-        if (m_window->isMaximized()) {
-            m_window->showNormal();
+    connect(maximizeButton, &StandardSystemButton::clicked, this, [this](){
+        if (window->isMaximized()) {
+            window->showNormal();
         } else {
-            m_window->showMaximized();
+            window->showMaximized();
         }
     });
-    m_closeButton = new StandardSystemButton(SystemButtonType::Close, q);
-    connect(m_closeButton, &StandardSystemButton::clicked, this, [this](){
-        if (m_hideWhenClose) {
-            m_window->hide();
+    closeButton = new StandardSystemButton(SystemButtonType::Close, q);
+    connect(closeButton, &StandardSystemButton::clicked, this, [this](){
+        if (hideWhenClose) {
+            window->hide();
         } else {
-            m_window->close();
+            window->close();
         }
     });
     // According to the title bar design guidance, the system buttons should always be
@@ -554,9 +364,9 @@ void StandardTitleBarPrivate::initialize()
     const auto systemButtonsInnerLayout = new QHBoxLayout;
     systemButtonsInnerLayout->setSpacing(0);
     systemButtonsInnerLayout->setContentsMargins(0, 0, 0, 0);
-    systemButtonsInnerLayout->addWidget(m_minimizeButton);
-    systemButtonsInnerLayout->addWidget(m_maximizeButton);
-    systemButtonsInnerLayout->addWidget(m_closeButton);
+    systemButtonsInnerLayout->addWidget(minimizeButton);
+    systemButtonsInnerLayout->addWidget(maximizeButton);
+    systemButtonsInnerLayout->addWidget(closeButton);
     const auto systemButtonsOuterLayout = new QVBoxLayout;
     systemButtonsOuterLayout->setSpacing(0);
     systemButtonsOuterLayout->setContentsMargins(0, 0, 0, 0);
@@ -567,13 +377,12 @@ void StandardTitleBarPrivate::initialize()
     titleBarLayout->setContentsMargins(0, 0, 0, 0);
     titleBarLayout->addStretch();
     titleBarLayout->addLayout(systemButtonsOuterLayout);
-    q->setLayout(titleBarLayout);
-    setTitleLabelAlignment(Qt::AlignLeft | Qt::AlignVCenter);
+    q->setTitleLabelAlignment(Qt::AlignLeft | Qt::AlignVCenter);
 #endif // Q_OS_MACOS
     retranslateUi();
     updateTitleBarColor();
     updateChromeButtonColor();
-    m_window->installEventFilter(this);
+    window->installEventFilter(this);
 }
 
 StandardTitleBar::StandardTitleBar(QWidget *parent)
@@ -583,134 +392,235 @@ StandardTitleBar::StandardTitleBar(QWidget *parent)
 
 StandardTitleBar::~StandardTitleBar() = default;
 
-Qt::Alignment StandardTitleBar::titleLabelAlignment() const
+#ifndef Q_OS_MACOS
+StandardSystemButton *StandardTitleBar::minimizeButton() const
 {
     Q_D(const StandardTitleBar);
-    return d->titleLabelAlignment();
+    return d->minimizeButton;
 }
 
-void StandardTitleBar::setTitleLabelAlignment(const Qt::Alignment value)
+StandardSystemButton *StandardTitleBar::maximizeButton() const
 {
-    Q_D(StandardTitleBar);
-    d->setTitleLabelAlignment(value);
+    Q_D(const StandardTitleBar);
+    return d->maximizeButton;
 }
 
-#ifndef Q_OS_MACOS
-StandardSystemButton *StandardTitleBar::minimizeButton() const
+StandardSystemButton *StandardTitleBar::closeButton() const
 {
     Q_D(const StandardTitleBar);
-    return d->m_minimizeButton;
+    return d->closeButton;
 }
+#endif // Q_OS_MACOS
 
-StandardSystemButton *StandardTitleBar::maximizeButton() const
+void StandardTitleBar::mouseReleaseEvent(QMouseEvent *event)
 {
-    Q_D(const StandardTitleBar);
-    return d->m_maximizeButton;
+    QWidget::mouseReleaseEvent(event);
+    Q_D(StandardTitleBar);
+    std::ignore = d->mouseEventHandler(event);
 }
 
-StandardSystemButton *StandardTitleBar::closeButton() const
+void StandardTitleBar::mouseDoubleClickEvent(QMouseEvent *event)
+{
+    QWidget::mouseDoubleClickEvent(event);
+    Q_D(StandardTitleBar);
+    std::ignore = d->mouseEventHandler(event);
+}
+
+Qt::Alignment StandardTitleBar::titleLabelAlignment() const
 {
     Q_D(const StandardTitleBar);
-    return d->m_closeButton;
+    return d->labelAlignment;
+}
+
+void StandardTitleBar::setTitleLabelAlignment(const Qt::Alignment value)
+{
+    Q_D(StandardTitleBar);
+    if (d->labelAlignment == value) {
+        return;
+    }
+    d->labelAlignment = value;
+    update();
+    Q_EMIT titleLabelAlignmentChanged();
 }
-#endif // Q_OS_MACOS
 
 bool StandardTitleBar::isExtended() const
 {
     Q_D(const StandardTitleBar);
-    return d->isExtended();
+    return d->extended;
 }
 
 void StandardTitleBar::setExtended(const bool value)
 {
     Q_D(StandardTitleBar);
-    d->setExtended(value);
+    if (d->extended == value) {
+        return;
+    }
+    d->extended = value;
+    setFixedHeight(d->extended ? kDefaultExtendedTitleBarHeight : kDefaultTitleBarHeight);
+    Q_EMIT extendedChanged();
 }
 
 bool StandardTitleBar::isHideWhenClose() const
 {
     Q_D(const StandardTitleBar);
-    return d->isHideWhenClose();
+    return d->hideWhenClose;
 }
 
 void StandardTitleBar::setHideWhenClose(const bool value)
 {
     Q_D(StandardTitleBar);
-    d->setHideWhenClose(value);
+    if (d->hideWhenClose == value) {
+        return;
+    }
+    d->hideWhenClose = value;
+    Q_EMIT hideWhenCloseChanged();
 }
 
 ChromePalette *StandardTitleBar::chromePalette() const
 {
     Q_D(const StandardTitleBar);
-    return d->chromePalette();
+    return d->chromePalette;
+}
+
+void StandardTitleBar::paintEvent(QPaintEvent *event)
+{
+    Q_ASSERT(event);
+    if (!event) {
+        return;
+    }
+    Q_D(StandardTitleBar);
+    if (!d->window) {
+        return;
+    }
+    const bool active = d->window->isActiveWindow();
+    const QColor backgroundColor = (active ?
+        d->chromePalette->titleBarActiveBackgroundColor() :
+        d->chromePalette->titleBarInactiveBackgroundColor());
+    const QColor foregroundColor = (active ?
+        d->chromePalette->titleBarActiveForegroundColor() :
+        d->chromePalette->titleBarInactiveForegroundColor());
+    QPainter painter(this);
+    painter.save();
+    painter.setRenderHints(QPainter::Antialiasing |
+        QPainter::TextAntialiasing | QPainter::SmoothPixmapTransform);
+    painter.fillRect(QRect(QPoint(0, 0), size()), backgroundColor);
+    if (d->titleLabelVisible) {
+        const QString text = d->window->windowTitle();
+        if (!text.isEmpty()) {
+            painter.setPen(foregroundColor);
+            painter.setFont(d->titleFont.value_or(d->defaultFont()));
+            const auto pos = [this, d]() -> QPoint {
+                const StandardTitleBarPrivate::FontMetrics labelSize = d->titleLabelSize();
+                const int titleBarWidth = width();
+                int x = 0;
+                if (d->labelAlignment & Qt::AlignLeft) {
+                    x = (d->windowIconRect().right() + kDefaultTitleBarContentsMargin);
+                } else if (d->labelAlignment & Qt::AlignRight) {
+                    x = (titleBarWidth - kDefaultTitleBarContentsMargin - labelSize.width);
+#ifndef Q_OS_MACOS
+                    x -= (titleBarWidth - d->minimizeButton->x());
+#endif // Q_OS_MACOS
+                } else if (d->labelAlignment & Qt::AlignHCenter) {
+                    x = std::round(qreal(titleBarWidth - labelSize.width) / qreal(2));
+                } else {
+                    WARNING << "The alignment for the title label is not set!";
+                }
+                const int y = std::round((qreal(height() - labelSize.height) / qreal(2)) + qreal(labelSize.ascent));
+                return {x, y};
+            }();
+            painter.drawText(pos, text);
+        }
+    }
+    if (d->windowIconVisible) {
+        const QIcon icon = d->window->windowIcon();
+        if (!icon.isNull()) {
+            icon.paint(&painter, d->windowIconRect());
+        }
+    }
+    painter.restore();
+    event->accept();
 }
 
 bool StandardTitleBar::titleLabelVisible() const
 {
     Q_D(const StandardTitleBar);
-    return d->titleLabelVisible();
+    return d->titleLabelVisible;
 }
 
 void StandardTitleBar::setTitleLabelVisible(const bool value)
 {
     Q_D(StandardTitleBar);
-    d->setTitleLabelVisible(value);
+    if (d->titleLabelVisible == value) {
+        return;
+    }
+    d->titleLabelVisible = value;
+    update();
+    Q_EMIT titleLabelVisibleChanged();
 }
 
 QSize StandardTitleBar::windowIconSize() const
 {
     Q_D(const StandardTitleBar);
-    return d->windowIconSize();
+    return d->windowIconSize.value_or(kDefaultWindowIconSize);
 }
 
 void StandardTitleBar::setWindowIconSize(const QSize &value)
 {
+    Q_ASSERT(!value.isEmpty());
+    if (value.isEmpty()) {
+        return;
+    }
+    if (windowIconSize() == value) {
+        return;
+    }
     Q_D(StandardTitleBar);
-    d->setWindowIconSize(value);
+    d->windowIconSize = value;
+    update();
+    Q_EMIT windowIconSizeChanged();
 }
 
 bool StandardTitleBar::windowIconVisible() const
 {
     Q_D(const StandardTitleBar);
-    return d->windowIconVisible();
+    return d->windowIconVisible;
 }
 
 void StandardTitleBar::setWindowIconVisible(const bool value)
 {
     Q_D(StandardTitleBar);
-    d->setWindowIconVisible(value);
+    if (d->windowIconVisible == value) {
+        return;
+    }
+    d->windowIconVisible = value;
+    update();
+    Q_EMIT windowIconVisibleChanged();
+#ifndef Q_OS_MACOS
+    // Ideally we should use FramelessWidgetsHelper::get(this) everywhere, but sadly when
+    // we call it here, it may be too early that FramelessWidgetsHelper has not attached
+    // to the top level widget yet, and thus it will trigger an assert error (the assert
+    // should not be suppressed, because it usually indicates there's something really
+    // wrong). So here we have to use the top level widget directly, as a special case.
+    // NOTE: In your own code, you should always use FramelessWidgetsHelper::get(this)
+    // if possible.
+    FramelessWidgetsHelper::get(d->window)->setHitTestVisible(d->windowIconRect(), d->windowIconVisible_real());
+#endif // Q_OS_MACOS
 }
 
 QFont StandardTitleBar::titleFont() const
 {
     Q_D(const StandardTitleBar);
-    return d->titleFont();
+    return d->titleFont.value_or(QFont());
 }
 
 void StandardTitleBar::setTitleFont(const QFont &value)
 {
+    if (titleFont() == value) {
+        return;
+    }
     Q_D(StandardTitleBar);
-    d->setTitleFont(value);
-}
-
-void StandardTitleBar::paintEvent(QPaintEvent *event)
-{
-    Q_D(StandardTitleBar);
-    d->paintTitleBar(event);
-}
-
-void StandardTitleBar::mouseReleaseEvent(QMouseEvent *event)
-{
-    QWidget::mouseReleaseEvent(event);
-    Q_D(StandardTitleBar);
-    std::ignore = d->mouseEventHandler(event);
-}
-
-void StandardTitleBar::mouseDoubleClickEvent(QMouseEvent *event)
-{
-    QWidget::mouseDoubleClickEvent(event);
-    Q_D(StandardTitleBar);
-    std::ignore = d->mouseEventHandler(event);
+    d->titleFont = value;
+    update();
+    Q_EMIT titleFontChanged();
 }
 
 FRAMELESSHELPER_END_NAMESPACE