In Firefox 81, we have improved error messages for extension developers and updated user-facing notifications to provide more information on how extensions are modifying their settings.
For developers, the menus.create API now provides more meaningful error messages when supplying invalid match or url patterns. This updated message should make it easier for developers to quickly identify and fix the error. In addition, webNavigation.getAllFrames and webNavigation.getFrame will return a promise resolved with null in case the tab is discarded, which is how these APIs behave in Chrome.
For users, we’ve added a notification when an add-on is controlling the “Ask to save logins and passwords for websites” setting, using the privacy.services.passwordSavingEnabled settings API. Users can see this notification in their preferences or by navigating to about:preferences#privacy.
Thank you Deepika Karanji for improving the error messages, and our WebExtensions and security engineering teams for making these changes possible. We’re looking forward to seeing what is next for Firefox 82.