Firefox 3.5.3 does not find any plugins
AMD Phenom2x4, 2.6.28-15-generic
If you're using 64bit ubuntu, the default plugins installed from the repos won't work with the mozilla build (which is 32bit). see the ubuntuzilla faq for workarounds.
Why isn't the build 64bit?
because mozilla doesn't release 64bit builds. ubuntuzilla installs what mozilla provides...
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