575268 - Sites using static overlays scroll very slowly with Direct2D enabled

Status: RESOLVED INCOMPLETE

(Firefox :: General, defect)

Description

[Michael Marley]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 6.1; Win64; x64; en-US; rv:1.9.3a6pre) Gecko/20100628 Minefield/3.7a6pre
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 6.1; Win64; x64; en-US; rv:1.9.3a6pre) Gecko/20100628 Minefield/3.7a6pre

On sites that render a static (usually translucent) overlay over the main site content, scrolling using Direct2D in firefox is unbearably slow (even worse than with Direct2D off).  A good example of this can be seen at Facebook, where the FB Chat overlay causes slow scrolling.  However, any site with such a static overlay causes slowdowns.  Making the window smaller increases scrolling performance slightly, but it still remains quite slow.  If it matters, my PC is using an nvidia 8600m GT with driver 258.49 and a screen resolution of 1680x1050.

Reproducible: Always

Steps to Reproduce:
1.Enable Direct2D
2.Go to a site that uses a static overlay, such as Facebook.
3.

Comment 1

[Michael Marley]

As of the build on 7/1/2010, this seems to have drastically improved for some (but not all!) sites.  It would seem that sites using alpha-transparent images as the overlay are now fast, but sites, such as Facebook, using some other method (CSS/gradients?) are still just as slow as always.

Comment 2

[Tanner M [:Tannn3r]]

Reporter, can you still reproduce this bug in Firefox 6?

Please update to Firefox 6 or later, update your plugins, and retest in a new profile. If you still see the issue with the updated version of Firefox, please post here. Otherwise, please close as RESOLVED > WORKSFORME.

http://getfirefox.com/