diff --git a/src/plugins/platforms/cocoa/qcocoanativeinterface.h b/src/plugins/platforms/cocoa/qcocoanativeinterface.h
index 7f0b05002d..4a0cf11257 100644
--- a/src/plugins/platforms/cocoa/qcocoanativeinterface.h
+++ b/src/plugins/platforms/cocoa/qcocoanativeinterface.h
@@ -53,9 +53,6 @@ private:
     // deregisters.
     static void registerTouchWindow(QWindow *window,  bool enable);
 
-    // Set the size of the unified title and toolbar area.
-    static void setContentBorderThickness(QWindow *window, int topThickness, int bottomThickness);
-
     // Set the size for a unified toolbar content border area.
     // Multiple callers can register areas and the platform plugin
     // will extend the "unified" area to cover them.
diff --git a/src/plugins/platforms/cocoa/qcocoanativeinterface.mm b/src/plugins/platforms/cocoa/qcocoanativeinterface.mm
index 80bb504a75..e95a3c0331 100644
--- a/src/plugins/platforms/cocoa/qcocoanativeinterface.mm
+++ b/src/plugins/platforms/cocoa/qcocoanativeinterface.mm
@@ -65,8 +65,6 @@ QPlatformNativeInterface::NativeResourceForIntegrationFunction QCocoaNativeInter
         return NativeResourceForIntegrationFunction(QCocoaNativeInterface::registerTouchWindow);
     if (resource.toLower() == "setembeddedinforeignview")
         return NativeResourceForIntegrationFunction(QCocoaNativeInterface::setEmbeddedInForeignView);
-    if (resource.toLower() == "setcontentborderthickness")
-        return NativeResourceForIntegrationFunction(QCocoaNativeInterface::setContentBorderThickness);
     if (resource.toLower() == "registercontentborderarea")
         return NativeResourceForIntegrationFunction(QCocoaNativeInterface::registerContentBorderArea);
     if (resource.toLower() == "setcontentborderareaenabled")
@@ -139,16 +137,6 @@ void QCocoaNativeInterface::registerTouchWindow(QWindow *window,  bool enable)
         cocoaWindow->registerTouch(enable);
 }
 
-void QCocoaNativeInterface::setContentBorderThickness(QWindow *window, int topThickness, int bottomThickness)
-{
-    if (!window)
-        return;
-
-    QCocoaWindow *cocoaWindow = static_cast<QCocoaWindow *>(window->handle());
-    if (cocoaWindow)
-        cocoaWindow->setContentBorderThickness(topThickness, bottomThickness);
-}
-
 void QCocoaNativeInterface::registerContentBorderArea(QWindow *window, quintptr identifier, int upper, int lower)
 {
     if (!window)
diff --git a/src/plugins/platforms/cocoa/qcocoawindow.h b/src/plugins/platforms/cocoa/qcocoawindow.h
index 1e625ddb9c..7c1eec6e4a 100644
--- a/src/plugins/platforms/cocoa/qcocoawindow.h
+++ b/src/plugins/platforms/cocoa/qcocoawindow.h
@@ -158,7 +158,7 @@ public:
     void setWindowCursor(NSCursor *cursor);
 
     void registerTouch(bool enable);
-    void setContentBorderThickness(int topThickness, int bottomThickness);
+
     void registerContentBorderArea(quintptr identifier, int upper, int lower);
     void setContentBorderAreaEnabled(quintptr identifier, bool enable);
     void setContentBorderEnabled(bool enable) override;
diff --git a/src/plugins/platforms/cocoa/qcocoawindow.mm b/src/plugins/platforms/cocoa/qcocoawindow.mm
index e426f459b1..cb813114ef 100644
--- a/src/plugins/platforms/cocoa/qcocoawindow.mm
+++ b/src/plugins/platforms/cocoa/qcocoawindow.mm
@@ -1832,16 +1832,6 @@ void QCocoaWindow::registerTouch(bool enable)
         m_view.allowedTouchTypes &= ~NSTouchTypeMaskIndirect;
 }
 
-void QCocoaWindow::setContentBorderThickness(int topThickness, int bottomThickness)
-{
-    m_topContentBorderThickness = topThickness;
-    m_bottomContentBorderThickness = bottomThickness;
-    bool enable = (topThickness > 0 || bottomThickness > 0);
-    m_drawContentBorderGradient = enable;
-
-    applyContentBorderThickness();
-}
-
 void QCocoaWindow::registerContentBorderArea(quintptr identifier, int upper, int lower)
 {
     m_contentBorderAreas.insert(identifier, BorderRange(identifier, upper, lower));