Note that this addon requires the "Access your data for all websites" permission[0], which means:

> The extension can read the content of any web page you visit as well as data you enter into those web pages, such as usernames and passwords.

I'm sure the devs are super trustworthy, but there have been cases of legitimate extensions falling in the wrong hands, and this, coupled with automatic extension updates, could be a big security hole in your setup.

[0]: https://support.mozilla.org/en-US/kb/permission-request-mess...

PS: Ironically, the link above has utm elements.