diff --git a/src/wayland/meta-wayland-legacy-xdg-shell.c b/src/wayland/meta-wayland-legacy-xdg-shell.c
index e438f2460..eba802e0c 100644
--- a/src/wayland/meta-wayland-legacy-xdg-shell.c
+++ b/src/wayland/meta-wayland-legacy-xdg-shell.c
@@ -439,7 +439,7 @@ zxdg_toplevel_v6_set_fullscreen (struct wl_client   *client,
   if (output_resource)
     {
       MetaWaylandOutput *output = wl_resource_get_user_data (output_resource);
-      if (output)
+      if (output && output->logical_monitor)
         meta_window_move_to_monitor (window, output->logical_monitor->number);
     }
 
diff --git a/src/wayland/meta-wayland-xdg-shell.c b/src/wayland/meta-wayland-xdg-shell.c
index fefed4596..d8f639757 100644
--- a/src/wayland/meta-wayland-xdg-shell.c
+++ b/src/wayland/meta-wayland-xdg-shell.c
@@ -456,7 +456,7 @@ xdg_toplevel_set_fullscreen (struct wl_client   *client,
     {
       MetaWaylandOutput *output = wl_resource_get_user_data (output_resource);
 
-      if (output)
+      if (output && output->logical_monitor)
         {
           meta_window_move_to_monitor (window,
                                        output->logical_monitor->number);