The latest release is incompatible with Pale Moon 27
Created by: beerisgood
First, thanks for your addon and for Pale Moon support!
Unfortunately your addon doesn't work with Pale Moon 27. I can open the option window and it can be installed but it doesn't work - testet with your testsite.
Pale Moon 27 is currently in alpha stage but if you can get it work again, then that would be awesome! Here you can get the new version: https://www.palemoon.org/WIP/
Ah the reason is probably your addon is a jetpack addon, right? Pale Moon 27+ doesn't support Jetpack addons.