bug#50954: 28.0.60; Shift selection commands moves the mark with active region

[Eli Zaretskii]

> From: Stefan Kangas <stefan@marxist.se>
> Date: Sat, 2 Oct 2021 01:37:56 +0200
> 
> 0. emacs -Q
> 1. C-<SPC>
> 2. C-p
> 3. S-<up>
> 
> The result is that the first region, set in steps 1+2, is deactivated
> in step 3.  In other words, step 3 moves the mark to point, and then
> moves point up one line.
> 
> I expect that step 3 does not move the mark when there is an active region.

If this is what you expect, you want to customize shift-select-mode to
'permanent' (a new value in Emacs 28).  The "usual" expectations are
different, because shift-selection is documented to set mark.