Rated 1 out of 5 stars

How did you people manage to review this add-on? I can't even get it to install. I am trying to install on a Windows 10 PC with Firefox 58.0.1 and Thunderbird 52.6.0 - should be the latest version of both. All I get is: This add-on could not be installed because it has not been verified.

This review is for a previous version of the add-on (3.2.4.1).