Re: Set-window-vscroll sometimes doesn't work

[Eli Zaretskii]

> From: Yuan Fu <casouri@gmail.com>
> Date: Sun, 18 Oct 2020 15:12:10 -0400
> Cc: help-gnu-emacs@gnu.org
> 
> 1. Is it true that move_it_by_lines regards an image as one display line?

Yes.  That's why we need vscroll in the first place.

> 2. It seems that when I move focus out of the window, the vscroll setting is 
> nullified, why is that?

I don't know.  It doesn't happen here when I display a tall image and
scroll it with C-n/C-p.