Firefox 4 is the first release to support restartless add-ons: https://developer.mozilla.org/en/Extensions/Bootstrapped_extensions https://developer.mozilla.org

Firefox 4 is the first release to support restartless add-ons: https://developer.mozilla.org/en/Extensions/Bootstrapped_extensions https://developer.mozilla.org/en/Extensions/Bootstrapped_ext... Add-ons written in the traditional way will still need a restart, until the authors adapt them to the new bootstrap API. Here are some add-ons that are restartless already: https://addons.mozilla.org/firefox/tag/restartless https://addons.mozilla.org/firefox/tag/restartless