# HG changeset patch
# User sotaro <sotaro.ikeda.g@gmail.com>
# Date 1610634595 0
# Node ID c989e16ae8d0801b76efe712658abcbf3704a486
# Parent  dc0d1d98e111aa781333980c2561f534ea1ebb0b
Bug 1681107 - Fix race condition of calling CompositorBridgeChild::SendPause() r=rmader,stransky

Differential Revision: https://phabricator.services.mozilla.com/D101693

diff --git a/widget/gtk/nsWindow.cpp b/widget/gtk/nsWindow.cpp
--- a/widget/gtk/nsWindow.cpp
+++ b/widget/gtk/nsWindow.cpp
@@ -5085,23 +5085,29 @@ void nsWindow::NativeMoveResize() {
   if (mNeedsShow && mIsShown) {
     NativeShow(true);
   }
 }
 
 void nsWindow::PauseRemoteRenderer() {
 #ifdef MOZ_WAYLAND
   if (!mIsDestroyed) {
-    if (mContainer && moz_container_wayland_has_egl_window(mContainer)) {
+    if (mContainer) {
       // Because wl_egl_window is destroyed on moz_container_unmap(),
       // the current compositor cannot use it anymore. To avoid crash,
       // pause the compositor and destroy EGLSurface & resume the compositor
       // and re-create EGLSurface on next expose event.
-      MOZ_ASSERT(GetRemoteRenderer());
-      if (CompositorBridgeChild* remoteRenderer = GetRemoteRenderer()) {
+
+      // moz_container_wayland_has_egl_window() could not be used here, since
+      // there is a case that resume compositor is not completed yet.
+
+      CompositorBridgeChild* remoteRenderer = GetRemoteRenderer();
+      bool needsCompositorPause = !mNeedsCompositorResume && !!remoteRenderer &&
+                                  mCompositorWidgetDelegate;
+      if (needsCompositorPause) {
         // XXX slow sync IPC
         remoteRenderer->SendPause();
         // Re-request initial draw callback
         RefPtr<nsWindow> self(this);
         moz_container_wayland_add_initial_draw_callback(
             mContainer, [self]() -> void {
               self->mNeedsCompositorResume = true;
               self->MaybeResumeCompositor();