Subject: bug#23431: 25.0.93; EWW hangs

From: Eli Zaretskii <[email-masked]>
Date: Wed, 04 May 2016 05:34:28 +0300

> From: Lars Ingebrigtsen <[email-masked]>
> Cc: [email-masked],  [email-masked],  [email-masked]
> Date: Tue, 03 May 2016 21:37:42 +0200
> 
> Eli Zaretskii <[email-masked]> writes:
> 
> > Btw, if I wait for a while (maybe 20 sec), the slowness disappears,
> > and Emacs becomes responsive again, although the animation still goes
> > on.  So perhaps what causes this is some initial processing?  (I have
> > no idea what's involved in displaying an animated GIF.)
> 
> After Emacs has decoded all the frames in the image, they'll then be
> stored in the Emacs display image cache (the one you can clear with
> `clear-image-cache'), so Emacs should be responsive after the animated
> GIF has looped once.  (Unless there are more frames in the image than
> the length of the Emacs image cache.)

Which means that the heavy part is decoding, and not redisplay.