Mozilla late on November 1 released Firefox 220.127.116.11, an update it promised last week after it announced five bugs had been introduced by the previous version of the browser.
The update, which Mozilla has begun pushing to users who have enabled automatic updates, fixes multiple regression flaws. These include problems that crop up when code is changed to plug other holes, which developers spotted within days of Firefox 18.104.22.168's October 18 debut.
Last week, Mozilla's user interface designer, Mike Beltzner, confirmed that several regressions had popped up, including one rated as critical.
According to Bugzilla, Mozilla's bug-tracking database, however, at least one of the five problems hasn't been completely resolved. The regression that stymied Firefox extensions from updating and installing on some Windows, designated Bug 396695, lacks the usual "FIXED" label.
Developers created a patch, but then became convinced that more work was needed to rule out other, still-unpatched causes for the glitch. With time pressing, the decision was made to roll out the initial fix but keep working on the problem. "This is larger and riskier than we want to take in 22.214.171.124," said David Veditz on a Bugzilla thread.
"Leaving this bug open for additional work to be done," replied Roger Strong later in the ongoing discussion on Bugzilla.
The other four regression errors have been fixed, according to Bugzilla.
Firefox 126.96.36.199 can be downloaded from the Mozilla site in versions for Windows, Mac OS X and Linux.
This is the second time in 2007 that Mozilla has had to rush out an update to fix regressions that had crept into the browser.