4 files changed, 27 insertions, 11 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoamenu.mm b/src/plugins/platforms/cocoa/qcocoamenu.mm
index 0b03a98fd6..e88cc54143 100644
--- a/src/plugins/platforms/cocoa/qcocoamenu.mm
+++ b/src/plugins/platforms/cocoa/qcocoamenu.mm
@@ -294,9 +294,13 @@ void QCocoaMenu::syncSeparatorsCollapsible(bool enable)
 
         for (NSMenuItem *item in m_nativeMenu.itemArray) {
             if (item.separatorItem) {
-                if (auto *cocoaItem = qt_objc_cast<QCocoaNSMenuItem *>(item).platformMenuItem)
-                    cocoaItem->setVisible(!previousIsSeparator);
-                item.hidden = previousIsSeparator;
+                // hide item if previous was a separator, or if it's explicitly hidden
+                bool itemVisible = !previousIsSeparator;
+                if (auto *cocoaItem = qt_objc_cast<QCocoaNSMenuItem *>(item).platformMenuItem) {
+                    cocoaItem->setVisible(!previousIsSeparator && cocoaItem->isVisible());
+                    itemVisible = cocoaItem->isVisible();
+                }
+                item.hidden = !itemVisible;
             }
 
             if (!item.hidden) {
diff --git a/src/plugins/platforms/cocoa/qcocoamenuitem.h b/src/plugins/platforms/cocoa/qcocoamenuitem.h
index 029d29be9d..e6bbf14367 100644
--- a/src/plugins/platforms/cocoa/qcocoamenuitem.h
+++ b/src/plugins/platforms/cocoa/qcocoamenuitem.h
@@ -117,6 +117,7 @@ public:
     inline bool isMerged() const { return m_merged; }
     inline bool isEnabled() const { return m_enabled && m_parentEnabled; }
     inline bool isSeparator() const { return m_isSeparator; }
+    inline bool isVisible() const { return m_isVisible; }
 
     QCocoaMenu *menu() const { return m_menu; }
     MenuRole effectiveRole() const;
diff --git a/src/plugins/platforms/cocoa/qnsview_dragging.mm b/src/plugins/platforms/cocoa/qnsview_dragging.mm
index 978d73f7d9..a4e4ad2f62 100644
--- a/src/plugins/platforms/cocoa/qnsview_dragging.mm
+++ b/src/plugins/platforms/cocoa/qnsview_dragging.mm
@@ -297,7 +297,9 @@ static QPoint mapWindowCoordinates(QWindow *source, QWindow *target, QPoint poin
     QCocoaDrag* nativeDrag = QCocoaIntegration::instance()->drag();
     Q_ASSERT(nativeDrag);
     nativeDrag->exitDragLoop();
-    nativeDrag->setAcceptedAction(qt_mac_mapNSDragOperation(operation));
+    // for internal drag'n'drop, don't override the action the drop event accepted
+    if (!nativeDrag->currentDrag())
+        nativeDrag->setAcceptedAction(qt_mac_mapNSDragOperation(operation));
 
     // Qt starts drag-and-drop on a mouse button press event. Cococa in
     // this case won't send the matching release event, so we have to
diff --git a/src/plugins/platforms/cocoa/qnsview_mouse.mm b/src/plugins/platforms/cocoa/qnsview_mouse.mm
index b42f2d0e7e..8695cfc642 100644
--- a/src/plugins/platforms/cocoa/qnsview_mouse.mm
+++ b/src/plugins/platforms/cocoa/qnsview_mouse.mm
@@ -103,21 +103,14 @@
     if (!m_platformWindow)
         return;
 
-    // get m_buttons in sync
-    // Don't send frme strut events if we are in the middle of a mouse drag.
-    if (m_buttons != Qt::NoButton)
-        return;
-
     switch (theEvent.type) {
     case NSEventTypeLeftMouseDown:
-    case NSEventTypeLeftMouseDragged:
         m_frameStrutButtons |= Qt::LeftButton;
         break;
     case NSEventTypeLeftMouseUp:
          m_frameStrutButtons &= ~Qt::LeftButton;
          break;
     case NSEventTypeRightMouseDown:
-    case NSEventTypeRightMouseDragged:
         m_frameStrutButtons |= Qt::RightButton;
         break;
     case NSEventTypeRightMouseUp:
@@ -132,6 +125,22 @@
         break;
     }
 
+    // m_buttons can sometimes get out of sync with the button state in AppKit
+    // E.g if the QNSView where a drag starts is reparented to another window
+    // while the drag is ongoing, it will not get the corresponding mouseUp
+    // call. This will result in m_buttons to be stuck on Qt::LeftButton.
+    // Since we know which buttons was pressed/released directly on the frame
+    // strut, we can rectify m_buttons here so that we at least don't return early
+    // from the drag test underneath because of the faulty m_buttons state.
+    // FIXME: get m_buttons in sync with AppKit/NSEvent all over in QNSView.
+    m_buttons &= ~m_frameStrutButtons;
+
+    if (m_buttons != Qt::NoButton) {
+        // Don't send frame strut events if we are in the middle of
+        // a mouse drag that didn't start on the frame strut.
+        return;
+    }
+
     NSWindow *window = [self window];
     NSPoint windowPoint = [theEvent locationInWindow];