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I got the following error message;
"Firefox could not install the search plugin from "https://addons.mozilla.org/firefox/downloads/latest/4605/addon-4605-latest.xml?src=addon-detail" because an engine with the same name already exists".
Firefox 4.01 does not show it in add-ons list so cannot uninstall and reinstall. It worked fine in previous versions of Firefox. I will miss the convenience of being able to quickly go from TitanTv directly to IMDb search page. Hope you can fix it.