In the 2008 Bugzilla thread, a Skype product manager first claimed that the problems had been fixed, then promised to address the flaws. "We will start looking into the problem and we promise to fix it asap," said Peter Kalmstroem of Skype.
Today, Skype again said that the newest version of its software would install a bug-free version of the toolbar. "Based on our initial investigation, we know that downloading the new client will fix any compatibility issues for most users," said a Skype spokesman.
"We are working with Mozilla to ensure that there are no other compatibility issues and to optimize the Skype Toolbar for Firefox," the spokesman continued. "We are sorry for any inconvenience this has caused our users."
Mozilla has used the Firefox blocklist before to disable rogue or malware-infected add-ons, most recently in June 2010 when it barred a password-stealing extension that had slipped through its quality checks and made it into the browser's library.
The blocking of Skype Toolbar, however, appears to be the first time that Mozilla has blacklisted all versions of a legitimate add-on.
One Firefox developer defended the move by arguing that the toolbar's performance problem "undoes years of work that we've put in."
Kev Needham, Mozilla's distribution channel manager, used stronger words. "We've had past problems, and I think it's fair to say Skype qualifies as a repeat offender," Needham said in a Bugzilla entry last month.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers, and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer or subscribe to Gregg's RSS feed. His email address is firstname.lastname@example.org.
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