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Firefox 3.5 is available.
The Check For Updates link in Firefox is disabled in Ubuntu. Firefox should only be updated through the package-management system.
or install it directly:
install the following package: firefox-3.5. Firefox 3.5 will be installed alongside Firefox 3.0.
When you have installed the new package, a new icon will appear in Applications > Internet alongside your old Firefox icon. The name is based on the codename for the new Firefox release, so Firefox 3.5 was labelled Shiretoko Web Browser.
more details: https://help.ubuntu.com/community/FirefoxNewVersion
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