


Thunderbird users who use extensions may want to research whether these are compatible with the latest version prior to running the upgrade. Users who don't want to be upgraded at this point in time need to disable the updating functionality in the program this is done by disabling automatic updates in the settings and changing the setting to manual updates (under Options > Advanced > Update). The program is either upgraded automatically in the background if the default update settings have not been changed, or on user request. Thunderbird users who still run version 68 of the email client are upgraded to version 78.2.2 - the most recent version - automatically. The new version of the email client supports only MailExtensions and not classic extensions this invalidated all classic extensions that users had installed in the email client unless the extension developers would have created a compatible version of the extension in the meantime.
