[HOWTO] Make Firefox fast and more responsive

I use Firefox 3.5.3 for my day to day browsing on my Ubuntu Karmic Koala Alpha (with KDE 4.3) and recently I experienced tremendous slowdowns making it less fit for use. I use a lot of addons including Firebug and Greasemonkey and it is no surprise that Firefox is slower than one without any extensions. I cannot move to Google Chrome or Epiphany because of the dependency on various add-ons such as Adblock Plus, Lastpass, Greasemonkey, Firebug and others and so I had to look what I can do.

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