Developer reply by Dillinger
Rated 3 out of 5 stars
It was a lifesaver for me. Until... it stopped working! The function that I mostly used is to edit the Reference field. TB version 91.4.1 64bit.
The workaround that did the job for me (at least for once) was to move the email to a local folder, do the edit and then move back to the Gmail folder.
Please use the provided support email address for bug reports.
To create your own collections, you must have a Mozilla Add-ons account.