diff --git a/src/plugins/platforms/cocoa/qcocoawindow.mm b/src/plugins/platforms/cocoa/qcocoawindow.mm
index 0dec048..c6c562d 100644
--- a/src/plugins/platforms/cocoa/qcocoawindow.mm
+++ b/src/plugins/platforms/cocoa/qcocoawindow.mm
@@ -432,26 +432,27 @@ NSUInteger QCocoaWindow::windowStyleMask(Qt::WindowFlags flags)
     Qt::WindowType type = static_cast<Qt::WindowType>(int(flags & Qt::WindowType_Mask));
     NSInteger styleMask = NSBorderlessWindowMask;
 
-    if ((type & Qt::Popup) == Qt::Popup) {
-        if (!windowIsPopupType(type) && !(flags & Qt::FramelessWindowHint))
-            styleMask = (NSUtilityWindowMask | NSResizableWindowMask | NSClosableWindowMask |
-                         NSMiniaturizableWindowMask | NSTitledWindowMask);
-    } else {
-        // Filter flags for supported properties
-        flags &= Qt::WindowType_Mask | Qt::FramelessWindowHint | Qt::WindowTitleHint |
-                 Qt::WindowMinMaxButtonsHint | Qt::WindowCloseButtonHint;
-        if (flags == Qt::Window) {
-            styleMask = (NSResizableWindowMask | NSClosableWindowMask | NSMiniaturizableWindowMask | NSTitledWindowMask);
-        } else if ((flags & Qt::Dialog) == Qt::Dialog) {
-            if (window()->modality() == Qt::NonModal)
-                styleMask = NSResizableWindowMask | NSClosableWindowMask | NSTitledWindowMask;
-            else
-                styleMask = NSResizableWindowMask | NSTitledWindowMask;
-        } else if (!(flags & Qt::FramelessWindowHint)) {
-            if ((flags & Qt::Dialog) || (flags & Qt::WindowMaximizeButtonHint))
+
+    // Filter flags for supported properties
+    flags &= Qt::WindowType_Mask | Qt::FramelessWindowHint | Qt::WindowTitleHint |
+             Qt::WindowMinMaxButtonsHint | Qt::WindowCloseButtonHint | Qt::CustomizeWindowHint;
+
+    if((flags & Qt::FramelessWindowHint) == 0  && !windowIsPopupType(type))
+    {
+        styleMask = NSTitledWindowMask;
+        if ((flags & Qt::Tool) == Qt::Tool)
+            styleMask |= NSUtilityWindowMask;
+
+        if((flags & Qt::CustomizeWindowHint) == 0 )
+        {
+            styleMask |= NSClosableWindowMask;
+            if (!((flags & Qt::Dialog) == Qt::Dialog) && !((flags & Qt::Tool) == Qt::Tool))
+                styleMask |= NSResizableWindowMask | NSMiniaturizableWindowMask;
+        }
+        else
+        {
+            if (flags & Qt::WindowMaximizeButtonHint)
                 styleMask |= NSResizableWindowMask;
-            if (flags & Qt::WindowTitleHint)
-                styleMask |= NSTitledWindowMask;
             if (flags & Qt::WindowCloseButtonHint)
                 styleMask |= NSClosableWindowMask;
             if (flags & Qt::WindowMinimizeButtonHint)