The addon started to crash my Nightly 67. Not a problem at the moment since nightly is a testing build, but yet.
UPDATE: I updated Nightly, tried to reproduce it and failed myself, me dumb ass should've saved a crash report while I could) Used to crash while opening any site. Sorry to disturb you, like I said - a bug in a developer build isn't a bug yet. ¯\_(ツ)_/¯