Rated 5 out of 5 stars

apparently it doesn't work with google imap boxes under thunderbird 91.2.1 (64-Bit)?
developers, please investigate?

Emails get destroid: all header informations are gone after applying changes. The changed header infos appear instead as the email content... while the former content (email text) is gone!


Current workaround for me:
COPY the mail to change from the google imap mailbox to Thunderbirds local folders, change the header or whatever needs changing and copy it back to the google imap area.

Edit 2022
running TB 93. Issue no longer existent.

This review is for a previous version of the add-on (3.6). 

Can you send a bug report to the support mail address?
I have no problems with Gmail boxes.