Web browsers always look to strike a balance between speed and functionality, but not enough focus on the former can easily spoil a user’s experience. Mozilla has put a great deal of time and effort working speed improvements into the latest version of its Firefox browser but sometimes all that hard work is for naught due to slow add-ons from third-party developers. In an effort to raise awareness and to push developers to optimize their plugins, perhaps, Mozilla has published a list of the add-ons that slow down Firefox the most. Among the worst offenders are FoxLingo, AniWeather, FoxyTunes and Xmarks Sync. In a bit of irony, an add-on called “FastestFox” that is supposed to speed up browsing by simplifying repetitive tasks is No.8 on Mozilla’s list. If you’ve been experiencing some slowness in Firefox and are wondering which add-ons might be the culprit, hit the read link for Mozilla’s complete list.