On Linux, frame menu items are disabled, but their accelerator keys are still enabled

I define several top-frame main menu items with accelerator keys, e.g.:
“&Arrows\tCtrl-A”
to call on the Arrows menu item when pressing Ctrl-A .

On Windows, when a menu item is disabled, so is its accelerator key, but not so on Linux (Ubuntu & Fedora).

Is that how menu-defined accelerator keys work on Linux, or am I missing something?