diff --git a/src/compositor/compositor-private.h b/src/compositor/compositor-private.h
index acb8d3c22..0ebf3a439 100644
--- a/src/compositor/compositor-private.h
+++ b/src/compositor/compositor-private.h
@@ -66,8 +66,6 @@ void meta_switch_workspace_completed (MetaScreen    *screen);
 
 gboolean meta_begin_modal_for_plugin (MetaScreen       *screen,
                                       MetaPlugin       *plugin,
-                                      Window            grab_window,
-                                      Cursor            cursor,
                                       MetaModalOptions  options,
                                       guint32           timestamp);
 void     meta_end_modal_for_plugin   (MetaScreen       *screen,
diff --git a/src/compositor/compositor.c b/src/compositor/compositor.c
index 89235e641..9a864448e 100644
--- a/src/compositor/compositor.c
+++ b/src/compositor/compositor.c
@@ -412,8 +412,6 @@ meta_stage_is_focused (MetaScreen *screen)
 gboolean
 meta_begin_modal_for_plugin (MetaScreen       *screen,
                              MetaPlugin       *plugin,
-                             Window            grab_window,
-                             Cursor            cursor,
                              MetaModalOptions  options,
                              guint32           timestamp)
 {
@@ -424,10 +422,19 @@ meta_begin_modal_for_plugin (MetaScreen       *screen,
   MetaDisplay    *display    = meta_screen_get_display (screen);
   Display        *xdpy       = meta_display_get_xdisplay (display);
   MetaCompositor *compositor = display->compositor;
+  ClutterStage *stage;
+  Window grab_window;
+  Cursor cursor = None;
   gboolean pointer_grabbed = FALSE;
   gboolean keyboard_grabbed = FALSE;
   int result;
 
+  stage = CLUTTER_STAGE (meta_get_stage_for_screen (screen));
+  if (!stage)
+    return FALSE;
+
+  grab_window = clutter_x11_get_stage_window (stage);
+
   if (compositor->modal_plugin != NULL || display->grab_op != META_GRAB_OP_NONE)
     return FALSE;
 
diff --git a/src/compositor/meta-plugin.c b/src/compositor/meta-plugin.c
index daf582435..ba8b9cbd9 100644
--- a/src/compositor/meta-plugin.c
+++ b/src/compositor/meta-plugin.c
@@ -267,10 +267,6 @@ meta_plugin_destroy_completed (MetaPlugin      *plugin,
 /**
  * meta_plugin_begin_modal:
  * @plugin: a #MetaPlugin
- * @grab_window: the X window to grab the keyboard and mouse on
- * @cursor: the cursor to use for the pointer grab, or None,
- *          to use the normal cursor for the grab window and
- *          its descendants.
  * @options: flags that modify the behavior of the modal grab
  * @timestamp: the timestamp used for establishing grabs
  *
@@ -291,15 +287,13 @@ meta_plugin_destroy_completed (MetaPlugin      *plugin,
  */
 gboolean
 meta_plugin_begin_modal (MetaPlugin       *plugin,
-                         Window            grab_window,
-                         Cursor            cursor,
                          MetaModalOptions  options,
                          guint32           timestamp)
 {
   MetaPluginPrivate *priv = META_PLUGIN (plugin)->priv;
 
   return meta_begin_modal_for_plugin (priv->screen, plugin,
-                                      grab_window, cursor, options, timestamp);
+                                      options, timestamp);
 }
 
 /**
diff --git a/src/meta/meta-plugin.h b/src/meta/meta-plugin.h
index d2643c2a9..0587551c8 100644
--- a/src/meta/meta-plugin.h
+++ b/src/meta/meta-plugin.h
@@ -396,8 +396,6 @@ typedef enum {
 
 gboolean
 meta_plugin_begin_modal (MetaPlugin      *plugin,
-                         Window           grab_window,
-                         Cursor           cursor,
                          MetaModalOptions options,
                          guint32          timestamp);