bug#42655: 27.1; iconify-frame on a Lucid build may stuck the frame

[Tino Calancha]

On Thu, 6 Aug 2020, Eli Zaretskii wrote:

> Thanks.  Looks like we never get the MapNotify event from X windows?
> Can you verify that, either by running the xev utility or by setting a
> breakpoint in xterm.c:handle_one_xevent when MapNotify is handled, and
> repeating the recipe?

Set breakpoint at
xterm::8348
C-z ; frame is hidden
;; I select again the hidden frame
;; gdb doesn't jump to the breakpoint and the frame is 'cursed'
M-x
;; The frame wakes up and gdb reaches the breakpoint.