More than two ago Mozilla Firefox 2 browser was released. A lot of experts and users agreed that there were too few modifications and updates for changing "1" index of version for index "2". Other words it should be Firefox 1.6. It was rather marketing step to draw public attention. At that time Opera 9 and Internet Explorer 7 were very serious competitors for old Firefox 1.5.
It was possible to download alpha-version of Firefox 3.0 in 6 weeks after version 2.0 released. The final 3.0 release was available in June 2008. And now after a year of hard developing version 3.5 is ready.
The greatest part of modifications was bug fixing that were received from the testers' bug reports. Browser security, personalization, usability were updated. Performance and ability to develop adds-in were improved. Almost all add-ons that are possible to run in Firefox 3, are not run in Firefox 3.5.
These days new update 3.5.6 for Firefox was released. The list of changes contains mostly bugs fixing and security improvement.
It is possible to download Firefox 3.5.6 for various operational systems from the official site of the project: