Rated 4 out of 5 stars

Great plugin! However, could you support Thunderbird 84 beta version? Since when I upgraded to macOS Big Sur, the thunderbird version 78 is sloooow and works fine when I use TB84 beta version.

This review is for a previous version of the add-on (0.7.7). 

I understand that TB 78 is not usable for you and TB 84 beta works for you. I'm sorry that you had such a bad experience with TB 78.

However, given that a lot of things change in each TB beta version of the course of a year, we are not able to constantly update to all betas. We can only provide compatibility support for officially supported end user releases. We have clearly marked the compatibility here on this site, to openly communicate this to users what we can do and what we cannot do.

While I understand that it's unfortunate in your particular case, I hope for your understanding.

P.S. Have you tried to override the version check and see whether Owl happens to work in TB 84 anyways?