bug#48409: Text runs away before user can copy it

[Eli Zaretskii <eliz@gnu.org>]

> From: 積丹尼 Dan Jacobson
>  <jidanni@jidanni.org>
> Date: Fri, 14 May 2021 14:32:54 +0800
> 
> Do e.g.,
> M-! cat /etc/motd
> 
> OK now in the minibuffer are several lines of juicy text.
> 
> Now grab the mouse and attempt to copy that text.
> 
> Alas, upon clicking, the text disappears.
> 
> Pro users know better, but average bumpkin users will be frustrated.
> 
> So maybe have the minibuffer stay put / stay open during this sequence of events.

Please RTFM.  The doc string of M-! says, inter alia:

  If COMMAND ends in ‘&’, execute it asynchronously.
  The output appears in the buffer ‘*Async Shell Command*’.
  That buffer is in shell mode.  You can also use
  ‘async-shell-command’ that automatically adds ‘&’.

  Otherwise, COMMAND is executed synchronously.  The output appears in
  the buffer ‘*Shell Command Output*’.  If the output is short enough to
  display in the echo area (which is determined by the variables
  ‘resize-mini-windows’ and ‘max-mini-window-height’), it is shown
  there, but it is nonetheless available in buffer ‘*Shell Command
  Output*’ even though that buffer is not automatically displayed.

(The user manual has a similar text.)

So the text you want is still available in an Emacs buffer, and you
can take it from there.

Closing.