Subject: bug#75056: 31.0.50; tty-child-frames with server / multiple clients possible hangs

From: Eli Zaretskii <[email-masked]>
Date: Sun, 26 Jan 2025 10:29:06 +0200

> From: Gerd Möllmann <[email-masked]>
> Cc: martin rudalics <[email-masked]>,  [email-masked],
>   [email-masked]
> Date: Sun, 26 Jan 2025 09:12:17 +0100
> 
> Eli Zaretskii <[email-masked]> writes:
> 
> >> Yes. C-x 5 2 can make a new root frame, and only one is visible on
> >> the display.
> >
> > So only the top root frame now returns visible = t?
> 
> Yes.
> 
> (Where "top" in that case is not a z-order thing, but all root frames on
> a tty are just part of the frame lists in parallel to each other, like
> before child frames. AFAIR, something in tty_display_info
> says who owns the terminal.)

So it is still true that a frame other than the top frame returns t
from frame-visible-p, right?  Here's the recipe:

  emacs -Q -nw
  C-x 5 b RET
  M-: (frame-visible-p (next-frame)) RET
   => t

This is different from GUI frames, in that z-order is not considered
on TTYs.