> 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"

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

This might be the actual problem as a speedbar-window is no longer a frame on it's own but embedded into an existing frame and the last visible frame must no be deleted with delete-frame.

Am Mo., 23. Juni 2025 um 13:50 Uhr schrieb Eli Zaretskii <eliz@gnu.org>:

> From: Johann Höchtl <johann.hoechtl@gmail.com>
> Date: Mon, 23 Jun 2025 13:24:14 +0200
>
> When I open a speedbar-window and right-click with the mouse on the status-bar, the speed-bar
> disappears.

What do you mean by "status bar" here? I tried right-clicking on
various portions of the Speedbar frame, but couldn't cause it to
"disappear".

> When I try to bring it back with speedbar-window I get the error message (in messages):
> "funcall-interactively: Attempt to delete the sole visible or iconified frame"

Doesn't happen here, either.

> I think there sould be a way to bring back that "invisible frame".

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"?

Thanks.