Mozilla retires Firefox 4 from security support

Unnoticed in the Tuesday release of Firefox 5 was Mozilla's decision to retire Firefox 4, the browser it shipped just three months ago.
As part of Tuesday's Firefox 5 release , Mozilla spelled out vulnerabilities it had patched in that edition and in 2010's Firefox 3.6, but it made no mention of any bugs fixed in Firefox 4.
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That's because Firefox 4 has reached what Mozilla calls EOL, for "end of life," for vulnerability patches.