Subject: bug#78221: 31.0.50; Improving *-change-functions notifications

From: Eli Zaretskii <[email-masked]>
Date: Sat, 03 May 2025 17:45:22 +0300

> Date: Sat, 3 May 2025 14:13:40 +0000
> Cc: [email-masked], Eli Zaretskii <[email-masked]>,
>   João Távora <[email-masked]>,
>   Ihor Radchenko <[email-masked]>, [email-masked]
> From: Alan Mackenzie <[email-masked]>
> 
> before/after-change-functions functions SHOULDN'T themselves make
> changes to the buffer text (apart from text properties).

That's not how nested notifications happen in most, if not all, the
cases.  They happen because a function that calls the before-change at
the beginning and an after-change at the end calls, as part of its
processing, some other function, which itself modifies buffer text or
the text properties, and thus emits its own "nested" notifications.