Firefox 3.0 recorded usage share of web browsers. Estimates of Firefox 3.0's global market share were generally in the range of 4–5%, and then dropped as users migrated to Firefox 3.5 and later Firefox 3.6. Partially as a result of this, between mid-December 2009 and the end of January 2010, Firefox 3.5 was the most popular browser (when counting individual browser versions), passing Internet Explorer 7. Mozilla ended support for Firefox 3 on March 30, 2010 with the release of 3.0.19. Firefox 3.0 was developed under the codename "Gran Paradiso". This, like other Firefox codenames, is the name of an actual place;
Firefox Firefox's Javascript performance on Kraken and the newer Jetstream tests trailing slightly behind all other tested browsers except Internet Explorer, which performed relatively poorly. On Octane, Firefox came ahead of IE and Safari, but again slightly behind the rest, including Vivaldi and Microsoft Edge. Edge took overall first place on the Jetstream and Octane benchmarks. As of the adoption of Firefox 57 and Mozilla's Quantum project entering production browsers in November 2017, Firefox was tested to be faster than Chrome in independent JavaScript tests, and demonstrated to use less memory with many browser tabs opened. Downloads have continued at an