bug#63344: 29.0.90; (shr-zoom-image) doesn't zoom to buffer size

[Eli Zaretskii]

> From: Pankaj Jangid <pankaj@codeisgreat.org>
> Date: Sun, 07 May 2023 12:26:49 +0530
> 
> 
> (shr-zoom-image) - The description says it cycles between the default
> size, the original size, and full-buffer size. But it never zooms to the
> full-buffer size.
> 
> Can I share attachment here? I have a 621kB screencast.

Please show a complete recipe for reproducing this issue, starting
from "emacs -Q".

There's no reason to post the screencast yet, perhaps we will be able
to reproduce this using some random image.  Unless you see this only
with a particular image and no other.

Thanks.