manifest.json) with the
legacykey (which has been deprecated in Thunderbird 78):
bootstrap.js) as an entry point to the extension. The file defines four methods (
shutdown) from which all extension behaviour is controlled. These extensions can be installed/uninstalled and enabled/disabled without restarting Thunderbird, so they are sometimes called "restartless" extensions. They use an RDF manifest (
install.rdf) and require a restart of Thunderbird for installation/uninstallation, upgrading/downgrading and enabling/disabling.