Should mouse events be triggered on ancestors of disabled elements?

http://www.w3.org/TR/html51/semantics.html#concept-fe-disabled says:

"A form control that is disabled must prevent any click events that are
queued on the user interaction task source from being dispatched on the
element."

Does that mean that clicking on a disabled element avoids triggering
mousedown, mouseup and click events on their ancestors?
Chrome, Opera, IE and Edge *do* trigger event handlers set on ancestors,
though not when they're set on the disabled elements themselves. Firefox
currently never triggers those events, which is files at
https://bugzil.la/1220048.

Sebastian