Decision leaves Opera and Microsoft with the only 64-bit browsers, though Google will soon join the pack
Fans of the non-profit Mozilla Foundation have waited… and waited… and waited more still, for Mozilla’s popular Firefox browser to add 64-bit support. With pickup of 64-bit SKUs of Microsoft Corp.’s (MSFT) Windows operating system rapidly accelerating, it certainly seemed a 64-bit browser would be just around the corner.
Instead Mozilla has made the curious decision to pull the plug on the long-delayed project, while offering only small clues as to why the decision was made.
The announcement was posted by Mozilla Engineering Manager Benjamin Smedberg on the Bugzilla development page. He ordered Mozilla employees and community developers:
Please stop building windows 64 builds and tests.
As for why the he opted to pull the plug on 64-bit for now, he comments, “Many plugins are not available in 64-bit versions. The plugins that are available don’t work correctly in Firefox because we haven’t implemented things like windowproc hooking, which means that hangs are more common.”

Full Story: DailyTech – Mozilla Abandons 64-Bit Firefox Development for Windows for Now.