Thank you for digging deeper into this! There is a lot of useful
information. But,
Here's a video of flickering https://youtu.be/Is2ebMXjhxg:
 - Different MacBook (2019 I believe).
 - Terminal.app (The one which comes as a standard).
 - Simplest Emacs from http://emacsformacosx.com/
 - No tmux.
 - No advanced user customizations (it is not my laptop).
 - Only display-line-numbers-mode is enabled with 'visual type.

It is definitely not attached to Alacritty, but probably the same issue
with refresh vs frame rate updates.

On Thu, Sep 1, 2022 at 4:30 AM Eli Zaretskii <eliz@gnu.org> wrote:

> > From: Gerd Möllmann <gerd.moellmann@gmail.com>
> > Cc: kuragin@google.com,  57434@debbugs.gnu.org
> > Date: Thu, 01 Sep 2022 10:56:35 +0200
> >
> > Eli Zaretskii <eliz@gnu.org> writes:
> >
> > > I'm not sure I understand: what would the user send to the terminal in
> > > those hooks?
> >
> > They would send the begin-update/end-update control sequences.  That
> > would be ESC P <something> in the one proposal I mentioned.
> >
> > It would of course be better if we could do that automatically.
>
> Exactly.  I don't think it's reasonable to expect users to figure out
> what and when to send if we cannot figure that out ourselves.
>


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