by ChristophK (Developer) on Martie 18, 2026 · link permanent

I share your frustration. Unfortunately, there is no way to tell thunderbird addons that a addon should remain "compatible" indefinitely if it accesses an internal API such as filters.

Furthermore, there is no notification when an addon is no longer compatible with the newest version.

I have updated the compatible versions, it should work again.

Edit: It seems it is now possible to mark a version as compatible "forever", so I have done that. Here's hoping it will work...