bug#56682: locked narrowing

[Eli Zaretskii]

> Date: Wed, 30 Nov 2022 00:15:39 +0000
> From: Gregory Heytings <gregory@heytings.org>
> cc: 56682@debbugs.gnu.org, Eli Zaretskii <eliz@gnu.org>, 
>     Stefan Monnier <monnier@iro.umontreal.ca>
> 
> After looking at this closely, it turns out that the change in 1c837c42c2 
> doesn't do what it was meant to do.  Sigh...  Dmitry, can you confirm that 
> the following change fixes this?

??? You are reverting what I believe was a fix for bug#57207, right?  I
don't think we want that problem back, do we?

How did you reach the conclusion that the change doesn't do what it was
supposed to? please tell more about what you saw and your conclusions.