Mozilla on Tuesday announced that due to some perfromance issues in Firefox browser, it is going to kill the support for animated themes starting with Firefox 18.

Mozilla says that footer images need to be of the resolution 3000px by 100px and geader images should be of 3000px by 200px to ensure themes receive header heights and numerous screen resolutions and downloading these images takes lot of time which results in slowing down the performance of Firefox but this problem intensifies with animated themes as animated images are much larger in resolution and needs to alter by browser constantly.

This issue was actully named as bug ‘bugzilla’ last year in April. The original solution to fix this bug was to crop the pics according to the screen resolution when the brower starts. When small size images are downloaded when the browser starts, load time automatically improves but this solution had a negative impact: animated images were not taken into the account which slows down the performance of the Firefox.


Mozilla decided to carry out this action of killing the animated themes completely and there will be no support for animated images starting from Firefox 18. The company also said that this was an unintended consequence and there are few cases where when firefox is restarted, images will animate normally but now it is advised not to use animated themes.

Blame Retina

Mozilla does not particularly pointed out that this step has been taken due to the retina display but the company talked about 3000 width resolution and even Retina MacBook Pros has resolution colser to 3000.The company also pointed to other laptops having 2000+ width resolution range but still the same issue occurs in these laptops as well.

The step will undeniably make some die-hard Firefox fans little upset but Mozilla still thinks that animated themes features is not so vital for Firefox.Mozilla released an apology statement :

We understand that animated themes are very popular with some users, and people will be upset with this difficult decision. However, to keep Firefox performing optimally for the even greater number of users who care about speed, the decision was necessary. We would love to find a way to preserve animated themes, and are currently looking into alternative solutions. In the meantime, a workaround would be to install the Personas Shuffler, which will refresh your animated themes every time Firefox loads, keeping them animating continuously.

Let’s be truthful: Apple made the concept of higher resolution displays highly popular worldwide with its srtong marketing efforts. The issue was filed before the launch of Retina MacBook Pro, but it was resolved after the launch.

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