Mozilla Corp. released Firefox version 2.0.0.11 to fix a regression bug in version 2.0.0.10 that it had just released Monday. This is a stability update, which corrects a compatibility issue with some websites and extensions discovered in Firefox 2.0.0.10. Mozilla announced that it strongly recommends that all Firefox users upgrade to this latest release.

All editions of Firefox 2.0.0.10, for all platforms, break pages that include the Canvas element (a feature first used by Apple Inc. in its Safari browser, which allows Web site designers to dynamically render bitmap images in HTML).

"Customers are complaining because their Firefox automatically updated to 2.0.0.10 and now they can no longer order photo prints in our shop. I think this is a very serious problem and I hope it will be fixed immediately in a 2.0.0.11 update," a post by Mozilla's Klaus Reimer said prior to the stability release.

This is the first time ever Mozilla has released two versions of the open-source browser in the same week. In fact, Mozilla developers have already found a fix a day after 2.0.0.10 was released, but a few days were needed to prepare the official release.

"The bug affects a specific use case of the Canvas tag, which is not yet in wide use," said Mike Schroepfer, vice president of engineering at Mozilla. "We used our standard process of releasing a beta to tens of thousands of users and had no reports of this issue prior to the full release of 2.0.0.10. Once we became aware of the issue, we worked overtime to address it."

Mozilla's Firefox 3.0 beta, which was released last week, is not affected by the Canvas bug. The simplest way to update your Firefox browser is to click Help (in the menu) then choose "Check for Updates..."