diff --git a/user.js b/user.js
index 16dfb41..4d3c8aa 100644
--- a/user.js
+++ b/user.js
@@ -1746,9 +1746,6 @@ user_pref("network.manage-offline-status", false);
    // user_pref("toolkit.cosmeticAnimations.enabled", false);
 /* 5016: disable reload/stop animation (FF56+) ***/
    // user_pref("browser.stopReloadAnimation.enabled", true);
-/* 5017: set submenu delay in milliseconds. 0=instant while a small number allows
- * a mouse pass over menu items without any submenus alarmingly shooting out ***/
-user_pref("ui.submenuDelay", 150); // (hidden pref)
 /* 5018: set maximum number of daily bookmark backups to keep (default is 15) ***/
 user_pref("browser.bookmarks.max_backups", 2);
 /* 5020: control urlbar click behaviour (with defaults) ***/