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

[Tino Calancha]

On Thu, 6 Aug 2020, Bhavin Gandhi wrote:

> > Bhavin, have you started the Emacs session with `Emacs -Q`?
>
> No, this was a normal start with `emacs`.
> I had exactly the same behavior.
Thanks for the clarification.

> > here is the backtrace at the point when Emacs is stuck.
> This backtrace was created with `emacs -Q` as Eli suggested initially.
Thank you.  I hope Eli can get some hint from it.