1 files changed, 24 insertions, 6 deletions
diff --git a/src/plugins/platforms/xcb/qxcbwindow.cpp b/src/plugins/platforms/xcb/qxcbwindow.cpp
index 50711e75c3..8c096ddc74 100644
--- a/src/plugins/platforms/xcb/qxcbwindow.cpp
+++ b/src/plugins/platforms/xcb/qxcbwindow.cpp
@@ -2635,15 +2635,34 @@ bool QXcbWindow::startSystemMoveResize(const QPoint &pos, int corner)
     const xcb_atom_t moveResize = connection()->atom(QXcbAtom::_NET_WM_MOVERESIZE);
     if (!connection()->wmSupport()->isSupportedByWM(moveResize))
         return false;
+
     const QPoint globalPos = QHighDpi::toNativePixels(window()->mapToGlobal(pos), window()->screen());
+    bool startedByTouch = false;
 #ifdef XCB_USE_XINPUT22
-    if (connection()->startSystemMoveResizeForTouchBegin(m_window, globalPos, corner))
-        return true;
+    // ### FIXME QTBUG-53389
+    startedByTouch = connection()->startSystemMoveResizeForTouchBegin(m_window, globalPos, corner);
 #endif
-    return doStartSystemMoveResize(globalPos, corner);
-}
+    if (startedByTouch) {
+        if (connection()->isUnity() || connection()->isGnome()) {
+            // These desktops fail to move/resize via _NET_WM_MOVERESIZE (WM bug?).
+            connection()->abortSystemMoveResizeForTouch();
+            return false;
+        }
+        // KWin, Openbox, AwesomeWM have been tested to work with _NET_WM_MOVERESIZE.
+    } else { // Started by mouse press.
+        if (!connection()->hasXInput2() || connection()->xi2MouseEventsDisabled()) {
+            // Without XI2 we can't get button press/move/release events.
+            return false;
+        }
+        if (connection()->isUnity())
+            return false; // _NET_WM_MOVERESIZE on this WM is bouncy (WM bug?).
+
+        doStartSystemMoveResize(globalPos, corner);
+    }
 
-bool QXcbWindow::doStartSystemMoveResize(const QPoint &globalPos, int corner)
+    return true;
+}
+void QXcbWindow::doStartSystemMoveResize(const QPoint &globalPos, int corner)
 {
     const xcb_atom_t moveResize = connection()->atom(QXcbAtom::_NET_WM_MOVERESIZE);
     xcb_client_message_event_t xev;
@@ -2670,7 +2689,6 @@ bool QXcbWindow::doStartSystemMoveResize(const QPoint &globalPos, int corner)
     xcb_send_event(connection()->xcb_connection(), false, xcbScreen()->root(),
                    XCB_EVENT_MASK_SUBSTRUCTURE_REDIRECT | XCB_EVENT_MASK_SUBSTRUCTURE_NOTIFY,
                    (const char *)&xev);
-    return true;
 }
 
 // Sends an XEmbed message.