Mozilla giving slow add-ons the old heave-ho

Slow performing add-ons be gone! Over on the Mozila blog the company has announced several new measures to try and ensure better performance from slow Firefox add-ons.

According to Mozilla add-ons product manager Justin Scott, each add-on installed on Firefox can slow the start-up time of the browser by as much as 10%. This percentage will obviously be different for various hardware configurations but based on Mozilla’s testing, installing 10 add-ons could literally double the start-up time of the Firefox browser.

Firefox performance is extremely important to our users, especially how quickly it starts up and loads websites. Many users don’t realize add-ons can cause these delays, and that’s why we’re committed to improving performance in a big way.

So what is Mozilla going to do to tackle slow Firefox add-ons?

It all comes down to weekly testing of popular add-ons, running them through benchmarks and posting the results online for all to see. This plus reaching out to developers and even giving them warnings if their add-ons fall below a certain threshold of performance:

Automated performance testing — Every week, we perform automated performance tests of the top 100 add-ons hosted in our gallery and display the results. Soon, we will automatically scan new versions of all add-ons as they are submitted. In the coming months, we will expand this to include other measures, such as page load time.

Slow performance warnings — In the next two weeks, we’ll begin displaying warnings in our gallery for any add-on that slows Firefox start-up time by 25% or more. We think users deserve to know when an add-on will impact them and want them to make an informed decision to install the add-on. In an upcoming version of Firefox, these warnings will be displayed in the Add-ons Manager as well.

Performance documentation and outreach — We’ve updated our Performance Best Practices and have begun reaching out to developers of slow add-ons and asking them to work on performance. This isn’t limited to add-ons hosted in our gallery; it includes all slow add-ons we can find.

On-demand performance testing — In the coming months, we’ll provide tools for developers to upload an add-on and receive a performance report to test the effectiveness of their fixes on the same machines that officially rate their performance.

Required opt-in for installation — It’s an all-too-common practice of third-party software to install toolbars and other bundled add-ons in your browser without permission. We know that these add-ons account for many of the performance problems reported to us, and users often don’t know how the add-on got there or how to remove it. In an upcoming version of Firefox, third party add-ons will not be installed unless the user explicitly allows the installation in Firefox. We expect this to have a huge impact on Firefox performance, as well as giving users back the control they should have over their add-ons.