diff --git a/include/FramelessHelper/Widgets/framelesswidgetshelper.h b/include/FramelessHelper/Widgets/framelesswidgetshelper.h
index 826b9ed..65ed1c5 100644
--- a/include/FramelessHelper/Widgets/framelesswidgetshelper.h
+++ b/include/FramelessHelper/Widgets/framelesswidgetshelper.h
@@ -60,6 +60,7 @@ public Q_SLOTS:
     void setTitleBarWidget(QWidget *widget);
     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 showSystemMenu(const QPoint &pos);
     void windowStartSystemMove2(const QPoint &pos);
diff --git a/include/FramelessHelper/Widgets/private/framelesswidgetshelper_p.h b/include/FramelessHelper/Widgets/private/framelesswidgetshelper_p.h
index 222d571..def5f81 100644
--- a/include/FramelessHelper/Widgets/private/framelesswidgetshelper_p.h
+++ b/include/FramelessHelper/Widgets/private/framelesswidgetshelper_p.h
@@ -52,6 +52,7 @@ public:
     void attachToWindow();
     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 showSystemMenu(const QPoint &pos);
     void windowStartSystemMove2(const QPoint &pos);
     void windowStartSystemResize2(const Qt::Edges edges, const QPoint &pos);
diff --git a/include/FramelessHelper/Widgets/private/standardsystembutton_p.h b/include/FramelessHelper/Widgets/private/standardsystembutton_p.h
index 4fc440e..c8a6fb4 100644
--- a/include/FramelessHelper/Widgets/private/standardsystembutton_p.h
+++ b/include/FramelessHelper/Widgets/private/standardsystembutton_p.h
@@ -28,6 +28,7 @@
 #include "standardsystembutton.h"
 #include <QtCore/qobject.h>
 #include <QtCore/qpointer.h>
+#include <optional>
 
 QT_BEGIN_NAMESPACE
 class QEnterEvent;
@@ -65,6 +66,7 @@ public:
     Q_NODISCARD QColor getActiveForegroundColor() const;
     Q_NODISCARD QColor getInactiveForegroundColor() const;
     Q_NODISCARD bool isActive() const;
+    Q_NODISCARD int iconSize2() const;
 
     void setHovered(const bool value);
     void setPressed(const bool value);
@@ -74,6 +76,7 @@ public:
     void setActiveForegroundColor(const QColor &value);
     void setInactiveForegroundColor(const QColor &value);
     void setActive(const bool value);
+    void setIconSize2(const int value);
 
     void enterEventHandler(QT_ENTER_EVENT_TYPE *event);
     void leaveEventHandler(QEvent *event);
@@ -94,6 +97,7 @@ private:
     bool m_hovered = false;
     bool m_pressed = false;
     bool m_active = false;
+    std::optional<int> m_iconSize2 = std::nullopt;
 };
 
 FRAMELESSHELPER_END_NAMESPACE
diff --git a/include/FramelessHelper/Widgets/private/standardtitlebar_p.h b/include/FramelessHelper/Widgets/private/standardtitlebar_p.h
index 58a8ea1..1501f04 100644
--- a/include/FramelessHelper/Widgets/private/standardtitlebar_p.h
+++ b/include/FramelessHelper/Widgets/private/standardtitlebar_p.h
@@ -77,6 +77,12 @@ public:
     Q_NODISCARD QFont titleFont() const;
     void setTitleFont(const QFont &value);
 
+    void mouseEventHandler(const QMouseEvent *event);
+
+    Q_NODISCARD QRect windowIconRect() const;
+    Q_NODISCARD bool windowIconVisible_real() const;
+    Q_NODISCARD bool isInTitleBarIconArea(const QPoint &pos) const;
+
 public Q_SLOTS:
     void updateMaximizeButton();
     void updateTitleBarColor();
@@ -100,9 +106,10 @@ private:
     bool m_hideWhenClose = false;
     QScopedPointer<ChromePalette> m_chromePalette;
     bool m_titleLabelVisible = true;
-    QSize m_windowIconSize = {};
+    std::optional<QSize> m_windowIconSize = std::nullopt;
     bool m_windowIconVisible = false;
     std::optional<QFont> m_titleFont = std::nullopt;
+    bool m_closeTriggered = false;
 };
 
 FRAMELESSHELPER_END_NAMESPACE
diff --git a/include/FramelessHelper/Widgets/standardsystembutton.h b/include/FramelessHelper/Widgets/standardsystembutton.h
index f2f6401..aaa9ae7 100644
--- a/include/FramelessHelper/Widgets/standardsystembutton.h
+++ b/include/FramelessHelper/Widgets/standardsystembutton.h
@@ -49,6 +49,7 @@ class FRAMELESSHELPER_WIDGETS_API StandardSystemButton : public QAbstractButton
     Q_PROPERTY(QColor activeForegroundColor READ activeForegroundColor WRITE setActiveForegroundColor NOTIFY activeForegroundColorChanged FINAL)
     Q_PROPERTY(QColor inactiveForegroundColor READ inactiveForegroundColor WRITE setInactiveForegroundColor NOTIFY inactiveForegroundColorChanged FINAL)
     Q_PROPERTY(bool active READ isActive WRITE setActive NOTIFY activeChanged FINAL)
+    Q_PROPERTY(int iconSize2 READ iconSize2 WRITE setIconSize2 NOTIFY iconSize2Changed FINAL)
 
 public:
     explicit StandardSystemButton(QWidget *parent = nullptr);
@@ -66,6 +67,7 @@ public:
     Q_NODISCARD QColor activeForegroundColor() const;
     Q_NODISCARD QColor inactiveForegroundColor() const;
     Q_NODISCARD bool isActive() const;
+    Q_NODISCARD int iconSize2() const;
 
 public Q_SLOTS:
     void setButtonType(const Global::SystemButtonType value);
@@ -78,6 +80,7 @@ public Q_SLOTS:
     void setActiveForegroundColor(const QColor &value);
     void setInactiveForegroundColor(const QColor &value);
     void setActive(const bool value);
+    void setIconSize2(const int value);
 
 protected:
     void enterEvent(QT_ENTER_EVENT_TYPE *event) override;
@@ -95,6 +98,7 @@ Q_SIGNALS:
     void activeForegroundColorChanged();
     void inactiveForegroundColorChanged();
     void activeChanged();
+    void iconSize2Changed();
 
 private:
     QScopedPointer<StandardSystemButtonPrivate> d_ptr;
diff --git a/include/FramelessHelper/Widgets/standardtitlebar.h b/include/FramelessHelper/Widgets/standardtitlebar.h
index 63b1a01..69dfa34 100644
--- a/include/FramelessHelper/Widgets/standardtitlebar.h
+++ b/include/FramelessHelper/Widgets/standardtitlebar.h
@@ -86,6 +86,8 @@ public:
 
 protected:
     void paintEvent(QPaintEvent *event) override;
+    void mouseReleaseEvent(QMouseEvent *event) override;
+    void mouseDoubleClickEvent(QMouseEvent *event) override;
 
 Q_SIGNALS:
     void extendedChanged();
diff --git a/src/widgets/framelesswidgetshelper.cpp b/src/widgets/framelesswidgetshelper.cpp
index 5b5572b..2c50d53 100644
--- a/src/widgets/framelesswidgetshelper.cpp
+++ b/src/widgets/framelesswidgetshelper.cpp
@@ -63,6 +63,7 @@ struct WidgetsHelperData
     QPointer<QWidget> minimizeButton = nullptr;
     QPointer<QWidget> maximizeButton = nullptr;
     QPointer<QWidget> closeButton = nullptr;
+    QList<QRect> hitTestVisibleRects = {};
 };
 
 struct WidgetsHelper
@@ -310,6 +311,26 @@ void FramelessWidgetsHelperPrivate::setHitTestVisible(QWidget *widget, const boo
     }
 }
 
+void FramelessWidgetsHelperPrivate::setHitTestVisible(const QRect &rect, const bool visible)
+{
+    Q_ASSERT(rect.isValid());
+    if (!rect.isValid()) {
+        return;
+    }
+    const QMutexLocker locker(&g_widgetsHelper()->mutex);
+    WidgetsHelperData *data = getWindowDataMutable();
+    if (!data) {
+        return;
+    }
+    const bool exists = data->hitTestVisibleRects.contains(rect);
+    if (visible && !exists) {
+        data->hitTestVisibleRects.append(rect);
+    }
+    if (!visible && exists) {
+        data->hitTestVisibleRects.removeAll(rect);
+    }
+}
+
 void FramelessWidgetsHelperPrivate::attachToWindow()
 {
     QWidget * const window = getWindow();
@@ -535,6 +556,13 @@ bool FramelessWidgetsHelperPrivate::isInTitleBarDraggableArea(const QPoint &pos)
             }
         }
     }
+    if (!data.hitTestVisibleRects.isEmpty()) {
+        for (auto &&rect : qAsConst(data.hitTestVisibleRects)) {
+            if (rect.isValid()) {
+                region -= rect;
+            }
+        }
+    }
     return region.contains(pos);
 }
 
@@ -824,6 +852,16 @@ void FramelessWidgetsHelper::setHitTestVisible(QWidget *widget, const bool visib
     d->setHitTestVisible(widget, visible);
 }
 
+void FramelessWidgetsHelper::setHitTestVisible(const QRect &rect, const bool visible)
+{
+    Q_ASSERT(rect.isValid());
+    if (!rect.isValid()) {
+        return;
+    }
+    Q_D(FramelessWidgetsHelper);
+    d->setHitTestVisible(rect, visible);
+}
+
 void FramelessWidgetsHelper::showSystemMenu(const QPoint &pos)
 {
     Q_D(FramelessWidgetsHelper);
diff --git a/src/widgets/standardsystembutton.cpp b/src/widgets/standardsystembutton.cpp
index 618ed45..57f2a95 100644
--- a/src/widgets/standardsystembutton.cpp
+++ b/src/widgets/standardsystembutton.cpp
@@ -154,6 +154,11 @@ bool StandardSystemButtonPrivate::isActive() const
     return m_active;
 }
 
+int StandardSystemButtonPrivate::iconSize2() const
+{
+    return m_iconSize2.value_or(FramelessManagerPrivate::getIconFont().pointSize());
+}
+
 void StandardSystemButtonPrivate::setHovered(const bool value)
 {
     if (m_hovered == value) {
@@ -287,6 +292,21 @@ void StandardSystemButtonPrivate::setActive(const bool value)
     Q_EMIT q->activeChanged();
 }
 
+void StandardSystemButtonPrivate::setIconSize2(const int value)
+{
+    Q_ASSERT(value > 0);
+    if (value <= 0) {
+        return;
+    }
+    if (iconSize2() == value) {
+        return;
+    }
+    m_iconSize2 = value;
+    Q_Q(StandardSystemButton);
+    q->update();
+    Q_EMIT q->iconSize2Changed();
+}
+
 void StandardSystemButtonPrivate::enterEventHandler(QT_ENTER_EVENT_TYPE *event)
 {
     Q_ASSERT(event);
@@ -343,7 +363,13 @@ void StandardSystemButtonPrivate::paintEventHandler(QPaintEvent *event)
             }
             return kDefaultBlackColor;
         }());
-        painter.setFont(FramelessManagerPrivate::getIconFont());
+        painter.setFont([this]() -> QFont {
+            QFont font = FramelessManagerPrivate::getIconFont();
+            if (m_iconSize2.has_value()) {
+                font.setPointSize(m_iconSize2.value());
+            }
+            return font;
+        }());
         painter.drawText(buttonRect, Qt::AlignCenter, m_code);
     }
     painter.restore();
@@ -360,11 +386,13 @@ void StandardSystemButtonPrivate::initialize()
     connect(q, &StandardSystemButton::released, this, [this](){ setPressed(false); });
 }
 
-StandardSystemButton::StandardSystemButton(QWidget *parent) : QAbstractButton(parent), d_ptr(new StandardSystemButtonPrivate(this))
+StandardSystemButton::StandardSystemButton(QWidget *parent)
+    : QAbstractButton(parent), d_ptr(new StandardSystemButtonPrivate(this))
 {
 }
 
-StandardSystemButton::StandardSystemButton(const SystemButtonType type, QWidget *parent) : StandardSystemButton(parent)
+StandardSystemButton::StandardSystemButton(const SystemButtonType type, QWidget *parent)
+    : StandardSystemButton(parent)
 {
     setButtonType(type);
 }
@@ -467,6 +495,12 @@ bool StandardSystemButton::isActive() const
     return d->isActive();
 }
 
+int StandardSystemButton::iconSize2() const
+{
+    Q_D(const StandardSystemButton);
+    return d->iconSize2();
+}
+
 void StandardSystemButton::setPressColor(const QColor &value)
 {
     Q_D(StandardSystemButton);
@@ -497,6 +531,12 @@ void StandardSystemButton::setActive(const bool value)
     d->setActive(value);
 }
 
+void StandardSystemButton::setIconSize2(const int value)
+{
+    Q_D(StandardSystemButton);
+    d->setIconSize2(value);
+}
+
 void StandardSystemButton::enterEvent(QT_ENTER_EVENT_TYPE *event)
 {
     QAbstractButton::enterEvent(event);
diff --git a/src/widgets/standardtitlebar.cpp b/src/widgets/standardtitlebar.cpp
index 0b3e35e..70fe903 100644
--- a/src/widgets/standardtitlebar.cpp
+++ b/src/widgets/standardtitlebar.cpp
@@ -25,8 +25,11 @@
 #include "standardtitlebar.h"
 #include "standardtitlebar_p.h"
 #include "standardsystembutton.h"
+#include "framelesswidgetshelper.h"
 #include <QtCore/qcoreevent.h>
+#include <QtCore/qtimer.h>
 #include <QtGui/qpainter.h>
+#include <QtGui/qevent.h>
 #include <QtWidgets/qboxlayout.h>
 
 FRAMELESSHELPER_BEGIN_NAMESPACE
@@ -144,9 +147,7 @@ void StandardTitleBarPrivate::paintTitleBar(QPaintEvent *event)
     if (m_windowIconVisible) {
         const QIcon icon = m_window->windowIcon();
         if (!icon.isNull()) {
-            const QSize size = (m_windowIconSize.isEmpty() ? kDefaultWindowIconSize : m_windowIconSize);
-            const int y = qRound(qreal(q->height() - size.height()) / qreal(2));
-            const QRect rect = {QPoint(kDefaultTitleBarContentsMargin, y), size};
+            const QRect rect = windowIconRect();
             titleLabelLeftOffset = (rect.left() + rect.width());
             icon.paint(&painter, rect);
         }
@@ -200,7 +201,7 @@ void StandardTitleBarPrivate::setTitleLabelVisible(const bool value)
 
 QSize StandardTitleBarPrivate::windowIconSize() const
 {
-    return m_windowIconSize;
+    return m_windowIconSize.value_or(kDefaultWindowIconSize);
 }
 
 void StandardTitleBarPrivate::setWindowIconSize(const QSize &value)
@@ -209,7 +210,7 @@ void StandardTitleBarPrivate::setWindowIconSize(const QSize &value)
     if (value.isEmpty()) {
         return;
     }
-    if (m_windowIconSize == value) {
+    if (windowIconSize() == value) {
         return;
     }
     m_windowIconSize = value;
@@ -229,6 +230,7 @@ void StandardTitleBarPrivate::setWindowIconVisible(const bool value)
         return;
     }
     m_windowIconVisible = value;
+    FramelessWidgetsHelper::get(m_window)->setHitTestVisible(windowIconRect(), windowIconVisible_real());
     Q_Q(StandardTitleBar);
     q->update();
     Q_EMIT q->windowIconVisibleChanged();
@@ -250,6 +252,82 @@ void StandardTitleBarPrivate::setTitleFont(const QFont &value)
     Q_EMIT q->titleFontChanged();
 }
 
+void StandardTitleBarPrivate::mouseEventHandler(const QMouseEvent *event)
+{
+    Q_ASSERT(event);
+    if (!event) {
+        return;
+    }
+    if (!m_window) {
+        return;
+    }
+    Q_Q(const StandardTitleBar);
+    const Qt::MouseButton button = event->button();
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+    const QPoint scenePos = event->scenePosition().toPoint();
+#else
+    const QPoint scenePos = event->windowPos().toPoint();
+#endif
+    const bool interestArea = isInTitleBarIconArea(scenePos);
+    switch (event->type()) {
+    case QEvent::MouseButtonRelease:
+        if (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,
+            // so we have to wait for a little bit to make sure the double
+            // click events are handled first, before we actually handle the
+            // mouse release events here.
+            // We need a copy of the "scenePos" variable here, otherwise it will
+            // soon fall out of scope when the lambda function actually runs.
+            QTimer::singleShot(150, this, [this, button, q, scenePos](){
+                // 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) {
+                    return;
+                }
+                FramelessWidgetsHelper::get(m_window)->showSystemMenu([button, q, &scenePos]() -> QPoint {
+                    if (button == Qt::LeftButton) {
+                        return {0, q->height()};
+                    }
+                    return scenePos;
+                }());
+            });
+        }
+        break;
+    case QEvent::MouseButtonDblClick:
+        if ((button == Qt::LeftButton) && interestArea) {
+            m_closeTriggered = true;
+            m_window->close();
+        }
+        break;
+    default:
+        break;
+    }
+}
+
+QRect StandardTitleBarPrivate::windowIconRect() const
+{
+    Q_Q(const StandardTitleBar);
+    const QSize size = windowIconSize();
+    const int y = qRound(qreal(q->height() - size.height()) / qreal(2));
+    return {QPoint(kDefaultTitleBarContentsMargin, y), size};
+}
+
+bool StandardTitleBarPrivate::windowIconVisible_real() const
+{
+    return (m_windowIconVisible && !m_window->windowIcon().isNull());
+}
+
+bool StandardTitleBarPrivate::isInTitleBarIconArea(const QPoint &pos) const
+{
+    if (!windowIconVisible_real()) {
+        return false;
+    }
+    return windowIconRect().contains(pos);
+}
+
 void StandardTitleBarPrivate::updateMaximizeButton()
 {
     const bool max = m_window->isMaximized();
@@ -515,4 +593,18 @@ void StandardTitleBar::paintEvent(QPaintEvent *event)
     d->paintTitleBar(event);
 }
 
+void StandardTitleBar::mouseReleaseEvent(QMouseEvent *event)
+{
+    QWidget::mouseReleaseEvent(event);
+    Q_D(StandardTitleBar);
+    d->mouseEventHandler(event);
+}
+
+void StandardTitleBar::mouseDoubleClickEvent(QMouseEvent *event)
+{
+    QWidget::mouseDoubleClickEvent(event);
+    Q_D(StandardTitleBar);
+    d->mouseEventHandler(event);
+}
+
 FRAMELESSHELPER_END_NAMESPACE