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CloseDeveloper reply by ChristophK
Rated 1 out of 5 stars
It is once again showing as incompatible with the current version.
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...
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