An ongoing project was started after Fx3.5 to improve startup time: https://wiki.mozilla.org/Firefox/Projects/Startup_Time_Improvements https://wiki.mozilla.org

An ongoing project was started after Fx3.5 to improve startup time: https://wiki.mozilla.org/Firefox/Projects/Startup_Time_Improvements https://wiki.mozilla.org/Firefox/Projects/Startup_Time_Impro... You can also read the blog of the lead engineer working on startup time improvement: http://autonome.wordpress.com/ http://autonome.wordpress.com/