Original URL: http://www.theregister.co.uk/2011/04/12/adblock_plus_man_pushes_back_on_mozilla_add_on_performance_tests/

AdBlock Plus man disputes Mozilla add-on tests

Slow Firefox startup list pared

By Cade Metz

Posted in Developer, 12th April 2011 22:43 GMT

Wladimir Palant – the man behind the most famous of Firefox add-ons, AdBlock Plus – has pushed back against Mozilla's recent efforts to rate the performance of his and other add-ons, claiming the outfit's testing methods were flawed.

As a result, Firefox has edited its public list that rates the startup performance of the most popular add-ons, and it's considering additional changes to its tests. "We just kicked off the first stage of the add-on performance initiative and are excited that our add-on developer community wants to help," add-ons product manager Justin Scott said in a statement sent to The Register. "We've seen developers submit bug reports and feature requests and we're already addressing some of the bugs filed."

Last week, with a blog post, Mozilla announced that it was beginning to crackdown on Firefox add-ons that put an undue drag on the performance of the open source browser. Mozilla said that it would soon add a warning to any add-on that slows Firefox's startup time by more than 25 per cent, and it publicly posted startup tests for the top 100 add-ons.

AdBlock Plus was number 12 on the list of worst performers, with Mozilla claiming it slowed Firefox startup times by 21 per cent. But in a series of blog posts, Palent questioned the accuracy of the list, and eventually submitted bugs fixes for the tests. Among other things, Palent pointed out that some add-ons were being tested while unpacked.

"There is probably a large number of Top 100 extensions that either didn’t make the list or got a better score due to testing framework bugs," he said. "And some other extensions probably got a worse score because of being run unpacked which in reality never happens in Firefox 4." Palent's full list of submitted bugs can be found here.

Following Palent's complaints, Mozilla edited its performance list to only include add-ons that slow startup performance by more than 25 per cent. And it is confident that all the add-ons on the list are indeed slowing startup performance. Until any problems are fixed with its tests, it will not display other performance warnings. The open source outfit will post additional information about its tests later this week. ®