Backed out changeset 3d48fba542df (bug 1667116) for bc failures on browser_startup_syncIPC.js CLOSED TREE

widget/gtk/nsWindow.cpp

@@ -7959,17 +7959,17 @@ void nsWindow::SetProgress(unsigned long progressPercent) {
 
 #ifdef MOZ_X11
 void nsWindow::SetCompositorHint(WindowComposeRequest aState) {
-  if (!mIsX11Display) {
-    return;
+  if (mIsX11Display &&
+      (!GetLayerManager() ||
+       GetLayerManager()->GetBackendType() == LayersBackend::LAYERS_BASIC)) {
+    gulong value = aState;
+    GdkAtom cardinal_atom = gdk_x11_xatom_to_atom(XA_CARDINAL);
+    gdk_property_change(gtk_widget_get_window(mShell),
+                        gdk_atom_intern("_NET_WM_BYPASS_COMPOSITOR", FALSE),
+                        cardinal_atom,
+                        32,  // format
+                        GDK_PROP_MODE_REPLACE, (guchar*)&value, 1);
   }
-
-  gulong value = aState;
-  GdkAtom cardinal_atom = gdk_x11_xatom_to_atom(XA_CARDINAL);
-  gdk_property_change(gtk_widget_get_window(mShell),
-                      gdk_atom_intern("_NET_WM_BYPASS_COMPOSITOR", FALSE),
-                      cardinal_atom,
-                      32,  // format
-                      GDK_PROP_MODE_REPLACE, (guchar*)&value, 1);
 }
 #endif