Skype is an awesome VoIP app. Firefox is still one of our favorite browsers. What happens when you put the two together? You get a buggy combination, Mozilla says.
"The current shipping version of the Skype Toolbar is one of the top crashers of Mozilla Firefox 3.6.13, and was involved in almost 40,000 crashes of Firefox last week," Mozilla stated in a blog post. "Additionally, depending on the version of the Skype Toolbar you're using, the methods it uses to detect and re-render phone numbers can make DOM manipulation up to 300 times slower, which drastically affects the page rendering times of a large percentage of Web content served today (plan English: to the user, it appears Firefox is slow loading Web pages)."
According to Mozilla, this constitutes a "major, user-facing issue" and meets the company's established criteria for blocking an add-on, which it's done. All versions of the Skype Toolbar, including beta releases, have been added to Firefox's blocklist.
Mozilla says this is a "soft block," meaning users are notified of what's happening and have the option of manually re-enabling the add-on. In the meantime, Mozilla said it's working with the Skype Toolbar team to "identify the issues that should be corrected, and will lift the soft block on future versions that address those issues."