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What's New in Firefox 1.5.0.1
Firefox 1.5.0.1 is a stability and security update that is part of our ongoing program to provide a safe Internet experience for our customers. We recommend that all users upgrade to this latest version.

Here's what's new in Firefox 1.5.0.1:
Improved stability.
Improved support for Mac OS X.
International Domain Name support for Iceland (.is) is now enabled.
Fixes for several memory leaks.
Several security enhancements.


http://www.mozilla.com/firefox/releases/1.5.0.1.html

Release Date: February 1, 2006