[gentoo-user] Gtk+ update results in slow Firefox

[Nikos Chantziaras]

There was an update to Gtk+ today (from 2.16.6 to 2.18.3).  After 
performing the update, Firefox (3.5.4) is slow as molasses when 
scrolling in some pages.  Example:

  http://www.simplemachines.org
(Try to scroll up/down).

Anyone else noticing this or is it just me?  I'm on AMD64.  I've rebuilt 
xulrunner and Firefox after the Gtk+ update just in case, but it didn't 
make any difference.