- Fixed: 627642 - Don't restore session into a new window if only the home page is open.
- Fixed: 636689 - Rename the HTML5 parser pref in order to reset it for everyone who has flipped it during the beta cycle.
- Fixed: 634590 - Unqualified function invocation doesn't use the global object the property was gotten from as |this|.
- Fixed: 4 bugs - Memory leak as long as quora.com is open.
- Fixed: 634855 - Memory leak with NoScript 126.96.36.199 installed.
- Fixed: 631733 - Footprint: When idle the GC holds on to unused chunks indefinitely.
- Fixed: 631951 - Footprint: interpret (some?) scripts a few times before compiling them.
- Fixed: 630932 - Footprint: High memory usage by the JS Engine even with no tabs open for > 12 hours.
- Fixed: 626602 - Implement background copying for windowless async plugins.
- Fixed: 635546 - [WinXP] No restart prompt after installing/updating non-restartless extensions and Java installed on the system.
- Fixed: 593372 - [Windows] Touchpad gestures don't work anymore with Elantech drivers.
- Fixed: 626214 - [Windows] Background tabs title is still hard to see.
- Fixed: 591687 - [Mac] Flash performance heavily degraded.
- Fixed: 580970 - [Linux] Tabs on top with Ubuntu Radiance and Ambiance looks less unified than it could.
Backed out to reduce risk for Firefox 4:
- Backed out: 355178 - Spell checker doesn't accept "scot-free" (tokenization, Hunspell 1.2.8).
- Backed out: 628179 - Navigation and tab switching should always hide the find bar.