Firefox 12 was released, not so surprisingly, just over a month after Firefox 11 was released. Usual updates come with it, but the best is probably their new update method. Instead of having User Account Control (if, for some very strange reason, you still have that enabled) prompt you every time Firefox wants to update, Firefox 12 has a method where you only need to go through UAC once and from there it won't prompt you for the update, but your computer will still stay secure.
What's new, changed, fixed, and still wrong, taken from the release notes, follows.
- Windows: Firefox is now easier to update with one less prompt (User Account Control)
- Page Source now has line numbers
- Line breaks are now supported in the title attribute
- Improvements to "Find in Page" to center search results
- URLs pasted into the download manager window are now automatically downloaded
- Various security fixes
- Some TinyMCE-based editors failed to load (739141)
- OS X: WebGL performance may be degraded on some hardware (713305)
- If you try to start Firefox using a locked profile, it will crash (see 573369)
- For some users, scrolling in the main GMail window will be slower than usual (see 579260)
- Some synaptic touch pads are unable to vertical scroll (see 622410)
- Windows: The use of Microsoft's System Restore functionality shortly after updating Firefox may prevent future updates (see 730285)