bug#47969: 28.0.50; Losing minibuffer focus in trying M-x command

[Gregory Heytings]

> I will attempt to - however I'm only seeing this behaviour once a week 
> or so, so difficult to replicate. My impression is that it used to 
> happen more frequently when I was running a build from git made spring 
> 2020, it's now less frequent but still occurring.

I think I managed to reproduce the issue you see:

emacs -Q
M-: (setq mouse-autoselect-window t)
C-x 2
move mouse to the upper window
ESC
move mouse to the lower window
xgnus

"x" is interpreted correctly and becomes M-x, but "gnus" is typed in the 
buffer in the lower window.

Could you confirm that this correctly reproduces what you see?