i use this on chrome ("Offered by: falken") at https://chrome.google.com/webstore/detail/advanced-font-settings/caclkomlalccbpcdllchkeecicepbmbm

But this firefox version appears to be empty. No settings. Can't use it if you can't configure it.

The text on this add-on page was lifted from the chrome add-on above. Is 'razza' the same person as 'falken'?

Deleted it. If you ever finish it, maybe I'll stumble on it again...