diff --git a/src/tests/monitor-unit-tests.c b/src/tests/monitor-unit-tests.c
index 80730a58f..2e0539fc1 100644
--- a/src/tests/monitor-unit-tests.c
+++ b/src/tests/monitor-unit-tests.c
@@ -226,11 +226,52 @@ check_test_client_state (MetaTestClient *test_client)
     }
 }
 
+static void
+check_test_client_x11_state (MetaTestClient *test_client)
+{
+  MetaMonitorManager *monitor_manager =
+    meta_backend_get_monitor_manager (test_backend);
+  MetaLogicalMonitor *primary_logical_monitor;
+  MetaMonitor *primary_monitor = NULL;
+  GError *error = NULL;
+
+  primary_logical_monitor =
+    meta_monitor_manager_get_primary_logical_monitor (monitor_manager);
+
+  if (primary_logical_monitor)
+    {
+      GList *monitors;
+
+      monitors = meta_logical_monitor_get_monitors (primary_logical_monitor);
+      primary_monitor = g_list_first (monitors)->data;
+    }
+
+  if (!meta_test_client_do (test_client, &error,
+                            "sync",
+                            NULL))
+    {
+      g_error ("Failed to sync test client '%s': %s",
+               meta_test_client_get_id (test_client), error->message);
+    }
+
+  if (!meta_test_client_do (test_client, &error,
+                            "assert_primary_monitor",
+                            primary_monitor
+                              ? meta_monitor_get_connector (primary_monitor)
+                              : "(none)",
+                              NULL))
+    {
+      g_error ("Failed to assert primary monitor in X11 test client '%s': %s",
+               meta_test_client_get_id (test_client), error->message);
+    }
+}
+
 static void
 check_monitor_test_clients_state (void)
 {
   check_test_client_state (wayland_monitor_test_client);
   check_test_client_state (x11_monitor_test_client);
+  check_test_client_x11_state (x11_monitor_test_client);
 }
 
 static void
diff --git a/src/wayland/meta-xwayland.c b/src/wayland/meta-xwayland.c
index 9a664afcb..406f8d218 100644
--- a/src/wayland/meta-xwayland.c
+++ b/src/wayland/meta-xwayland.c
@@ -1216,15 +1216,19 @@ meta_xwayland_set_primary_output (MetaX11Display *x11_display)
   MetaMonitorManager *monitor_manager =
     monitor_manager_from_x11_display (x11_display);
   XRRScreenResources *resources;
-  MetaLogicalMonitor *primary_monitor;
+  MetaLogicalMonitor *primary_logical_monitor;
+  GList *monitors;
+  MetaMonitor *primary_monitor;
   int i;
 
-  primary_monitor =
+  primary_logical_monitor =
     meta_monitor_manager_get_primary_logical_monitor (monitor_manager);
-
-  if (!primary_monitor)
+  if (!primary_logical_monitor)
     return;
 
+  monitors = meta_logical_monitor_get_monitors (primary_logical_monitor);
+  primary_monitor = g_list_first (monitors)->data;
+
   resources = XRRGetScreenResourcesCurrent (xdisplay,
                                             DefaultRootWindow (xdisplay));
   if (!resources)
@@ -1235,29 +1239,13 @@ meta_xwayland_set_primary_output (MetaX11Display *x11_display)
     {
       RROutput output_id = resources->outputs[i];
       XRROutputInfo *xrandr_output;
-      XRRCrtcInfo *crtc_info = NULL;
-      MtkRectangle crtc_geometry;
 
       xrandr_output = XRRGetOutputInfo (xdisplay, resources, output_id);
       if (!xrandr_output)
         continue;
 
-      if (xrandr_output->crtc)
-        crtc_info = XRRGetCrtcInfo (xdisplay, resources, xrandr_output->crtc);
-
-      XRRFreeOutputInfo (xrandr_output);
-
-      if (!crtc_info)
-        continue;
-
-      crtc_geometry.x = crtc_info->x;
-      crtc_geometry.y = crtc_info->y;
-      crtc_geometry.width = crtc_info->width;
-      crtc_geometry.height = crtc_info->height;
-
-      XRRFreeCrtcInfo (crtc_info);
-
-      if (mtk_rectangle_equal (&crtc_geometry, &primary_monitor->rect))
+      if (g_strcmp0 (xrandr_output->name,
+                     meta_monitor_get_connector (primary_monitor)) == 0)
         {
           XRRSetOutputPrimary (xdisplay, DefaultRootWindow (xdisplay),
                                output_id);