bug#40278: 27.0.90; Flickering in Windows 10

[Eli Zaretskii]

> From: Noam Postavsky <npostavs@gmail.com>
> Cc: Nicolas Bértolo <nicolasbertolo@gmail.com>,
>   40278@debbugs.gnu.org
> Date: Mon, 30 Mar 2020 12:23:42 -0400
> 
> I can see it here, especially on scroll towards the beginning of the
> file (Emacs is maxing out the CPU while doing this).

If redisplay cannot keep up, you could indeed see partially-redrawn
window.  But I didn't understand this was the problem, and it doesn't
sound like "flicker" to me.

> It kind of looks like the rectangle beneath the child frame gets
> repainted separately from the rest.

What do you mean by "beneath" in this context?