diff --git a/src/modules/wl_x11/e_mod_main.c b/src/modules/wl_x11/e_mod_main.c
--- a/src/modules/wl_x11/e_mod_main.c
+++ b/src/modules/wl_x11/e_mod_main.c
@@ -20,7 +20,7 @@
         return NULL;
      }
    root = ecore_x_window_root_first_get();
-   managed = !!ecore_x_window_prop_window_get(root, ECORE_X_ATOM_NET_SUPPORTING_WM_CHECK,
+   managed = -1 != ecore_x_window_prop_window_get(root, ECORE_X_ATOM_NET_SUPPORTING_WM_CHECK,
                                       &win, 1);
    e_comp_x_randr_canvas_new(ecore_x_window_root_first_get(), 1, 1);