Subject: Re: bug#78871: 31.0.50

From: Eli Zaretskii <[email-masked]>
Date: Mon, 23 Jun 2025 16:59:24 +0300

> From: Johann Höchtl <[email-masked]>
> Date: Mon, 23 Jun 2025 14:07:31 +0200
> Cc: [email-masked]
> 
> > It would be good to understand first what kind of "invisible frame" we
> are talking about.  Can you post a complete recipe starting from
> "emacs -Q"? 
> 
> Sure:
> 
> emacs -Q
> M-x speedbar-window
> Use the mouse and move over to the generated speedbar-window, move over anywhere the part where "#
> Files " (isn't that the status bar) is written and press right mouse button
> Effect: Speedbar Window disappears. 
> Any subsequent attempt to bring the speedbar (M-x speedbar) of the Windows (M-x speedbar-window) back
> results in the error message "Attempt to delete the sole visible or iconified frame"

Ah, okay.  This happens because mouse-3 on the mode line of the
speedbar window just deletes the speedbar window.  It should instead
call speedbar-window--close.  Patches welcome.

As a workaround, you can manually set the variable speedbar-frame to
nil:

  M-: (setq speedbar-frame nil) RET

Then "M-x speedbar-window" will work again.

> This error message also appears when you focus into the speedbar-window and press "Q" (which calls
> delete-frame). 

This is not a bug, since there is only one frame, and Emacs doesn't
allow to delete such a frame.