Update for Thunderbird 78

Required steps to update add-ons for Thunderbird 78.

Support for legacy WebExtensions was removed from Thunderbird Beta version 74, released in February 2020. Only modern WebExtensions are now compatible with Thunderbird 78.

Required Changes

There are two types of changes which are required to make your legacy extensions compatible with Thunderbird 78:

• The legacy WebExtension must be converted to a modern WebExtension

Convert legacy WebExtensions to modern WebExtensions

• All extensions need to be updated to reflect changes in Thunderbird core, like renamed/replaced API calls, removed support for some XUL elements and much more.

Adapt to Changes in Thunderbird 69-78

Additional Tips

Tips and Tricks