Users of Firefox 1.5 should plan to upgrade their browser by April 24 of next year at the very latest, according to Mozilla. That\u2019s because April 24 is the date developers plan to stop issuing security and stability fixes for the open-source browser, Mozilla said Wednesday in a note posted on the Mozilla.com website.This notice was included in an alert advertising the latest upgrade to Mozilla 1.5. Released Tuesday, the 18.104.22.168 update includes three critical security fixes for the browser. Firefox users should already have begun receiving the software through the browser\u2019s automatic update process.The April 24, 2007, date means that Firefox 1.5 users are being given a six-month window to move over to the Firefox 2.0 browser, released last month. This is the same amount of time that Firefox 1.0 users were given before updates for that product ceased.Version 22.214.171.124 also includes new software that will eventually allow Mozilla to push out its version 2 of the browser via Firefox\u2019s automatic update mechanism.Although Firefox 1.5 includes an automatic updater, it does not allow users to decline these software updates. So Mozilla has decided to add this capability in the 126.96.36.199 patch before offering the Firefox 2.0 as an automatic update. That way, users who are not ready to make the move to 2.0 will be able to decline the upgrade. Firefox representatives could not say when they plan to begin pushing version 2.0 as an automatic update.Mozilla developers are now beginning discussions on what to include in the Firefox 3.0 browser, which they hope to release one year from now, according to the Firefox roadmap.-Robert McMillan, IDG News Service (San Francisco Bureau)Related Links:\n\nMozilla Firefox Gaining Ground on Microsoft IE\n\nMozilla: We\u2019ll Fix 2nd Minor Firefox 2.0 Bug\n\nMozilla Firefox 2.0 Hits the Web\n\nMicrosoft Internet Explorer 7 Browser ReleasedCheck out our CIO News Alerts and Tech Informer pages for more updated news coverage.