Required steps to update add-ons for Thunderbird 102.
This section covers the required update steps for add-ons which are already compatible with Thunderbird 91 and need to be made compatible with Thunderbird 102.
Changes in WebExtension APIs
Our WebExtension APIs are meant to be stable, but we are adding new features and since this is a very young technology this might also require backward incompatible changes. All WebExtension API changes are listed in our API documentation:
MailExtensions can still run legacy code inside Experiments. Such legacy code has to be adjusted to changes made in Thunderbird Core. All known changes are listed in the following document: