diff --git a/common/flatpak-dir.c b/common/flatpak-dir.c
index e6e4d6fb..7d3374da 100644
--- a/common/flatpak-dir.c
+++ b/common/flatpak-dir.c
@@ -7139,6 +7139,8 @@ export_desktop_file (const char         *app,
                 g_string_append_printf (new_exec, " @@ %s @@", arg);
               else if (strcasecmp (arg, "%u") == 0)
                 g_string_append_printf (new_exec, " @@u %s @@", arg);
+              else if (strcmp (arg, "@@") == 0 || strcmp (arg, "@@u") == 0)
+                g_print (_("Skipping invalid Exec argument %s\n"), arg);
               else
                 g_string_append_printf (new_exec, " %s", arg);
             }