FocusScope: Also focus when the user clicks on tab widget background

Relevant when you don't have a title bar

src/private/widgets/TabWidgetWidget.cpp

@@ -88,6 +88,16 @@ void TabWidgetWidget::mouseDoubleClickEvent(QMouseEvent *ev)
     }
 }
 
+void TabWidgetWidget::mousePressEvent(QMouseEvent *ev)
+{
+    QTabWidget::mousePressEvent(ev);
+
+    if ((Config::self().flags() & Config::Flag_TitleBarIsFocusable) && !frame()->isFocused()) {
+        // User clicked on the tab widget itself
+        frame()->FocusScope::focus(Qt::MouseFocusReason);
+    }
+}
+
 void TabWidgetWidget::tabInserted(int)
 {
     onTabInserted();

src/private/widgets/TabWidgetWidget_p.h

@@ -42,6 +42,7 @@ public:
 protected:
     void paintEvent(QPaintEvent *) override;
     void mouseDoubleClickEvent(QMouseEvent *) override;
+    void mousePressEvent(QMouseEvent *) override;
     void tabInserted(int index) override;
     void tabRemoved(int index) override;
     bool isPositionDraggable(QPoint p) const override;