bug#43383: 26.3; `toggle-menu-bar-mode-from-frame'

[Eli Zaretskii]

> Date: Sun, 13 Sep 2020 20:58:16 +0000 (UTC)
> From: Drew Adams <drew.adams@oracle.com>
> 
> I don't understand the doc string:
> 
>  Toggle menu bar on or off, based on the status of the current frame.
>  See `menu-bar-mode' for more information.

Yes, the doc string "needs work".

> What's more, the doc string tells you to see the doc string of
> `menu-bar-mode'.  But that doesn't explain anything more about
> `toggle-menu-bar-mode-from-frame', e.g., how it differs from
> `menu-bar-mode'.  It's not even mentioned there.
> 
> What is this command - what's its use case?

If you set the menu-bar-lines parameter of a frame to zero, but don't
turn off menu-bar-mode, the menu bar will not be displayed.  In that
situation, "M-x menu-bar-mode RET" will do the exact opposite of what
you want, whereas this command, when invoked from the menu popped up
by C-mouse-3, will do what you expect.  That's the use case.