Subject: Re: bug#42653: Emacs now recentering very aggressively

From: Lars Ingebrigtsen <[email-masked]>
Date: Fri, 11 Sep 2020 12:29:04 +0200

Dale Sedivec <[email-masked]> writes:

> 2. Display anything in the header line: (setq-default header-line-format "foo"
[...]

> Expected behavior: Point is sitting at the bottom line of the window
> no matter how many times you page up
>
> Observed behavior: The window is recentered, usually after ever page
> up, with a slight delay

Ah!  So that's what this is.  I spent some time the other day tracking
down why this was happening in erc buffers, so I was looking at recent
erc changes.  But erc is one of the few modes I have with a header line
that I sometimes scroll back in, so that explains it.

> I can stop this from happening with (setq scroll-conservatively 101),
> so perhaps the behavior is intentional?  However, the fact that point
> stays at the bottom of the window for a brief instant, and then only
> recenters when (I am **guessing**) which-func-update runs leads me to
> believe this is unintentional behavior.

Yes, it's definitely unintentional.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no