Subject: Re: bug#22404: 25.1.50; Forcing `window-scroll-functions` to run.

From: Eli Zaretskii <[email-masked]>
Date: Tue, 09 Feb 2016 19:48:56 +0200

> Date:  Tue, 09 Feb 2016 08:00:33 -0800
> From:  Keith David Bershatsky <[email-masked]>
> Cc:  [email-masked]
> 
> The issue mentioned in my last email was caused by `font-lock-mode` -- when I turn off `font-lock-mode`, there are a few situations where point remains partially visible at the bottom of the window and redisplay does not catch it -- e.g., when the line that point is on is about 90 percent visible at the bottom of the window.

Did you define faces that change more than just the colors, like use a
different font or bold/italic typefaces?  If so, what you see might
not be a bug: the original display is before JIT font-lock kicks in
and changes the dimensions of the characters on display, so they are
partially visible only after fontifications did their job.