bug#56682: feature/improved-locked-narrowing 9dee6df39c: Reworked locked narrowing.

[Eli Zaretskii]

> From: Juri Linkov <juri@linkov.net>
> Cc: Gregory Heytings <gregory@heytings.org>,  56682@debbugs.gnu.org,
>   monnier@iro.umontreal.ca
> Date: Mon, 30 Jan 2023 19:24:56 +0200
> 
> For example, when there is at least one long line near the end of
> a diff-mode buffer, then sometimes the buffer gets truncated,
> 'diff-hunk-file-names' returns nil on diff headings,
> and there are a lot of such errors in the Messages buffer:
> 
>   Error during redisplay: (jit-lock-function 1) signaled (args-out-of-range 
> #<buffer *vc-diff*> 1118 1370)
>   ...
> 
> Maybe it's still possible to fix this?

We can and should fix this and other problems, but only if they are
reported.  Would you please file a bug report for any such problem you
find?