bug#44284: 27.1; with some Unicode font, scrolling upward with the mouse wheel actually scrolls downward when the cursor needs repositioning

[Eli Zaretskii]

> From: Vincent Lefevre <vincent@vinc17.net>
> Date: Wed, 28 Oct 2020 17:36:37 +0100
> 
> 
> Under Debian/unstable, create a file with
> 
>   printf "%d\n" `seq 1000` > file
> 
> then open it using GNU Emacs 27.1 with
> 
>   emacs -Q -fn 
> misc-fixed-medium-r-semicondensed--13-120-75-75-c-60-iso10646-1 file
> 
> Go to the end of the file with ESC > then scroll upward with the
> mouse wheel (button 4) several times (but slowly). When the cursor
> needs repositioning, this actually scrolls downward, probably
> because Emacs tries to center the mouse cursor instead of letting
> it at the bottom.

Please try the latest emacs-27 branch or the master, it's possible
that this is already fixed there.  (I couldn't verify myself if this
is fixed as I cannot reproduce the original problem to begin with.)

Thanks.