diff --git a/src/x11/window-props.c b/src/x11/window-props.c
index c0fc3804d..88c7beb70 100644
--- a/src/x11/window-props.c
+++ b/src/x11/window-props.c
@@ -607,12 +607,72 @@ reload_wm_name (MetaWindow    *window,
     }
 }
 
+static void
+meta_window_set_opaque_region (MetaWindow     *window,
+                               cairo_region_t *region)
+{
+  if (cairo_region_equal (window->opaque_region, region))
+    return;
+
+  g_clear_pointer (&window->opaque_region, cairo_region_destroy);
+
+  if (region != NULL)
+    window->opaque_region = cairo_region_reference (region);
+
+  meta_compositor_window_shape_changed (window->display->compositor, window);
+}
+
 static void
 reload_opaque_region (MetaWindow    *window,
                       MetaPropValue *value,
                       gboolean       initial)
 {
-  meta_window_x11_update_opaque_region (window);
+  cairo_region_t *opaque_region = NULL;
+
+  if (value->type != META_PROP_VALUE_INVALID)
+    {
+      gulong *region = value->v.cardinal_list.cardinals;
+      int nitems = value->v.cardinal_list.n_cardinals;
+
+      cairo_rectangle_int_t *rects;
+      int i, rect_index, nrects;
+
+      if (nitems % 4 != 0)
+        {
+          meta_verbose ("_NET_WM_OPAQUE_REGION does not have a list of 4-tuples.");
+          goto out;
+        }
+
+      /* empty region */
+      if (nitems == 0)
+        goto out;
+
+      nrects = nitems / 4;
+
+      rects = g_new (cairo_rectangle_int_t, nrects);
+
+      rect_index = 0;
+      i = 0;
+      while (i < nitems)
+        {
+          cairo_rectangle_int_t *rect = &rects[rect_index];
+
+          rect->x = region[i++];
+          rect->y = region[i++];
+          rect->width = region[i++];
+          rect->height = region[i++];
+
+          rect_index++;
+        }
+
+      opaque_region = cairo_region_create_rectangles (rects, nrects);
+
+      g_free (rects);
+    }
+
+ out:
+  meta_window_set_opaque_region (window, opaque_region);
+  cairo_region_destroy (opaque_region);
 }
 
 static void
diff --git a/src/x11/window-x11.c b/src/x11/window-x11.c
index 4b48342c9..76098ec5c 100644
--- a/src/x11/window-x11.c
+++ b/src/x11/window-x11.c
@@ -1585,76 +1585,6 @@ meta_window_x11_set_net_wm_state (MetaWindow *window)
     }
 }
 
-static void
-meta_window_set_opaque_region (MetaWindow     *window,
-                               cairo_region_t *region)
-{
-  if (cairo_region_equal (window->opaque_region, region))
-    return;
-
-  g_clear_pointer (&window->opaque_region, cairo_region_destroy);
-
-  if (region != NULL)
-    window->opaque_region = cairo_region_reference (region);
-
-  meta_compositor_window_shape_changed (window->display->compositor, window);
-}
-
-void
-meta_window_x11_update_opaque_region (MetaWindow *window)
-{
-  cairo_region_t *opaque_region = NULL;
-  gulong *region = NULL;
-  int nitems;
-
-  if (meta_prop_get_cardinal_list (window->display,
-                                   window->xwindow,
-                                   window->display->atom__NET_WM_OPAQUE_REGION,
-                                   &region, &nitems))
-    {
-      cairo_rectangle_int_t *rects;
-      int i, rect_index, nrects;
-
-      if (nitems % 4 != 0)
-        {
-          meta_verbose ("_NET_WM_OPAQUE_REGION does not have a list of 4-tuples.");
-          goto out;
-        }
-
-      /* empty region */
-      if (nitems == 0)
-        goto out;
-
-      nrects = nitems / 4;
-
-      rects = g_new (cairo_rectangle_int_t, nrects);
-
-      rect_index = 0;
-      i = 0;
-      while (i < nitems)
-        {
-          cairo_rectangle_int_t *rect = &rects[rect_index];
-
-          rect->x = region[i++];
-          rect->y = region[i++];
-          rect->width = region[i++];
-          rect->height = region[i++];
-
-          rect_index++;
-        }
-
-      opaque_region = cairo_region_create_rectangles (rects, nrects);
-
-      g_free (rects);
-    }
-
- out:
-  meta_XFree (region);
-
-  meta_window_set_opaque_region (window, opaque_region);
-  cairo_region_destroy (opaque_region);
-}
-
 static cairo_region_t *
 region_create_from_x_rectangles (const XRectangle *rects,
                                  int n_rects)
diff --git a/src/x11/window-x11.h b/src/x11/window-x11.h
index affd15e81..a2637a0df 100644
--- a/src/x11/window-x11.h
+++ b/src/x11/window-x11.h
@@ -55,7 +55,6 @@ void meta_window_x11_destroy_sync_request_alarm  (MetaWindow *window);
 void meta_window_x11_update_sync_request_counter (MetaWindow *window,
                                                   gint64      new_counter_value);
 
-void meta_window_x11_update_opaque_region        (MetaWindow *window);
 void meta_window_x11_update_input_region         (MetaWindow *window);
 void meta_window_x11_update_shape_region         (MetaWindow *window);