diff --git a/gdk/macos/gdkmacosglcontext.c b/gdk/macos/gdkmacosglcontext.c
index f50e837465..a8b28b05be 100644
--- a/gdk/macos/gdkmacosglcontext.c
+++ b/gdk/macos/gdkmacosglcontext.c
@@ -267,6 +267,34 @@ gdk_macos_gl_context_real_realize (GdkGLContext  *context,
   return TRUE;
 }
 
+static gboolean
+opaque_region_covers_surface (GdkMacosGLContext *self)
+{
+  GdkSurface *surface;
+  cairo_region_t *region;
+
+  g_assert (GDK_IS_MACOS_GL_CONTEXT (self));
+
+  surface = gdk_draw_context_get_surface (GDK_DRAW_CONTEXT (self));
+  region = GDK_MACOS_SURFACE (surface)->opaque_region;
+
+  if (region != NULL &&
+      cairo_region_num_rectangles (region) == 1)
+    {
+      cairo_rectangle_int_t extents;
+
+      cairo_region_get_extents (region, &extents);
+
+      if (extents.x == 0 &&
+          extents.y == 0 &&
+          extents.width == surface->width &&
+          extents.height == surface->height)
+        return TRUE;
+    }
+
+  return FALSE;
+}
+
 static void
 gdk_macos_gl_context_begin_frame (GdkDrawContext *context,
                                   cairo_region_t *painted)
@@ -315,6 +343,10 @@ gdk_macos_gl_context_begin_frame (GdkDrawContext *context,
       else
         opaque = FALSE;
 
+      /* If we are maximized, we might be able to make it opaque */
+      if (opaque == FALSE)
+        opaque = opaque_region_covers_surface (self);
+
       CGLSetParameter (cgl_context, kCGLCPSurfaceOpacity, &opaque);
 
       [self->gl_context update];
diff --git a/gdk/macos/gdkmacossurface-private.h b/gdk/macos/gdkmacossurface-private.h
index c366c0b4e6..8a5ee526fa 100644
--- a/gdk/macos/gdkmacossurface-private.h
+++ b/gdk/macos/gdkmacossurface-private.h
@@ -48,6 +48,7 @@ struct _GdkMacosSurface
   GdkMacosWindow *window;
   GPtrArray *monitors;
   cairo_region_t *input_region;
+  cairo_region_t *opaque_region;
   char *title;
 
   int root_x;
diff --git a/gdk/macos/gdkmacossurface.c b/gdk/macos/gdkmacossurface.c
index 61e249497e..5fe5bb38e7 100644
--- a/gdk/macos/gdkmacossurface.c
+++ b/gdk/macos/gdkmacossurface.c
@@ -98,9 +98,16 @@ static void
 gdk_macos_surface_set_opaque_region (GdkSurface     *surface,
                                      cairo_region_t *region)
 {
+  GdkMacosSurface *self = (GdkMacosSurface *)surface;
   NSView *nsview;
 
-  g_assert (GDK_IS_MACOS_SURFACE (surface));
+  g_assert (GDK_IS_MACOS_SURFACE (self));
+
+  if (region != self->opaque_region)
+    {
+      g_clear_pointer (&self->opaque_region, cairo_region_destroy);
+      self->opaque_region = cairo_region_copy (region);
+    }
 
   if ((nsview = _gdk_macos_surface_get_view (GDK_MACOS_SURFACE (surface))) &&
       GDK_IS_MACOS_CAIRO_VIEW (nsview))
@@ -386,6 +393,7 @@ gdk_macos_surface_destroy (GdkSurface *surface,
     }
 
   g_clear_pointer (&self->title, g_free);
+  g_clear_pointer (&self->opaque_region, cairo_region_destroy);
 
   if (window != NULL)
     [window close];