Sorry, that doesn't sound like any program that Mozilla has ever offered.

Perhaps it's not a program, but a feature already on my Firefox.....I don't use any other browser. Thanks

Firefox Options > Privacy. Check the settings.

Also at the bottom there is a box marked Clear History When Firefox Closes. Turn it on. Then on its far right, click the Settings button. Select anything you want removed when FF closes. On my system, I only have Cache selected.

Thanks, but that didn't do it. When it was working, there was a small Firefox icon in the lower right corner...it showed a pop-up when someone tried to load a cookie, described it and deleted it. Yahoo was trying to load cookies every 15 minutes or so, this feature alerted me and described the action as 'self-destructed'. Would like to get it back.... Thanks, Tedzo

that might have been this extension: https://addons.mozilla.org/firefox/addon/self-destructing-cookies/