bug#44180: 28.0.50; Emacs frames won't redisplay unless resized

[Eric Abrahamsen <eric@ericabrahamsen.net>]

martin rudalics <rudalics@gmx.at> writes:

>> The problem is that switching focus between windows (frames) does not
>> update which window is "live". The most-recently created, or
>> most-recently resized, window is always the live one. If I switch focus
>> to one of the other frames, it doesn't update, and I need to move it
>> around somehow in order to make it live. Then the other frames go dead.
>>
>> Before the breakage, it's possible that the non-visible frames were not
>> updated while they remained invisible, and I simply never knew because
>> I couldn't see them. Now they stay un-updated until I manipulate the
>> size of the window somehow.
>
> Do you get the corresponding focus events (whatever they are now) when
> you make another frame the fullscreen one?  If so, we should probably
> redraw the frame in that case.

I'm still not at the offending computer, but I think there's a high
likelihood of confusing myself with conflicting terminology here so,
just to be clear: this isn't proper fullscreening in the X11 sense. i3
also does that, but I hardly ever use it since the stacked layout is
close enough to full screen. In X11 terms I think all that's happening
is switching of focus between windows, it's just that i3's layout means
that the unfocused windows are always completely obscured. For some
reason Emacs now thinks that a window being obscured means that it's now
an icon. Switching focus back to that window does not un-iconify it.

Anyway, more later in the day...