At every new launch of FireFox version 12, a warning dialog pops up to advise that FireFox will no longer support this OS and the OS should be upgraded to mitigate security vulnerabilities. I am well aware of the risks and accept responsibility for not upgrading the OS or the browser to any higher version than what is presently installed.

Is there any way to continue using this version of FireFox and this OS, without this annoying message appearing at every launch and taking focus away from the browser? Selecting "never check for updates" within advanced options has not prevented the check and message at launch.