"So I just looked at the release notes for our 1.9a6 release, and they leave a lot to be desired from my point of view as a Gecko developer," Mozilla developer Boris Zbarsky wrote in a post to a discussion list. "They don't actually mention any of the major Gecko changes we'd like our alpha testers to bang on."
Gecko is the rendering engine that powers Firefox; changes to Gecko are a critical aspect of the Firefox 3 browser effort. Zbarsky alleged that the release notes simply indicate that there are over 90 bugs fixed but provide no clear indication of what is actually new from a Gecko point of view.
Beyond fixes and changes to Gecko, Firefox 3 Alpha 6 fixes a few other key features that the Firefox 3 development has previously introduced. Among them is an upgrade to the SQLite storage engine, which is the backbone for the new bookmarking and history feature called Places. Places itself also benefits from various fixes according to the nebulous release notes.
On the stability side, Alpha six has now added a new Quit dialog box that is expected to resolve termination errors without simply triggering a browser crash and/or restart.