Rated 5 out of 5 stars

Now that the issue with the 'c' shortcut in the message composer window seems to be fixed (see https://github.com/opto/nostalgy-xpi/issues/29), I would give it a full 5-stars!

Just the fact that the settings menu is somehwat "hidden" at the bottom of the Tools/Extras menu (which is faded out in TB by default) makes it a bit awkward to find. It should be moved to the "Add-on Settings" menu.

Apart from that, kudos to the developer! I think you managed to migrate an add-on to TB78+ that is essential, if not the most essential productivity add-on at all for many power users.

This review is for a previous version of the add-on (2.2.2). 

curious bug. Options is not in the addons options menu, because no icon is registered for the extension...
Thanks to TB people for pointing that out - the code is ok, only the (unrelated) icon missing.
With due time, I will add that.