Bug 1663003 [Linux/EGL] Use GLX to find X Visual for EGL as a workaround for https://gitlab.freedesktop.org/mesa/mesa/-/issues/149, r=jgilbert

Differential Revision: https://phabricator.services.mozilla.com/D89721

widget/gtk/nsWindow.cpp

@@ -4346,7 +4346,11 @@ nsresult nsWindow::Create(nsIWidget* aParent, nsNativeWidget aNativeParent,
         int visualId = 0;
         bool haveVisual;
 
-        if (!gfx::gfxVars::UseEGL()) {
+        // See https://bugzilla.mozilla.org/show_bug.cgi?id=1663003
+        // We need to use GLX to get visual even on EGL until
+        // EGL can provide compositable visual:
+        // https://gitlab.freedesktop.org/mesa/mesa/-/issues/149
+        if ((true /* !gfx::gfxVars::UseEGL() */)) {
           auto display = GDK_DISPLAY_XDISPLAY(gtk_widget_get_display(mShell));
           int screenNumber = GDK_SCREEN_XNUMBER(screen);
           haveVisual = GLContextGLX::FindVisual(