Both Firefox 3.0 and Firefox 3.5 are listed in the MInt repros. Just search through Synaptic Manager and install either or both.
Firefox 3.5 will be listed as Shiretoko Web browser in the Mint Menu.
Firefox 3.5.6 is the official current release of Firefox at the moment.
But several people, I know, are testing the even newer, still in development, versions of Firefox.
Firefox 3.6 is in Beta 4 and I am testing Firefox 3.7 is at a pre-Alpha 1 ... very very fast and, so far, quite stable for me.
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