Developer reply by Josh Geenen
Rated 3 out of 5 stars
When set “extensions.strictCompatibility” (configuration editor) to “false” then it still doesn't work properly. Settings dialog is transparent so it is hard to confirm changes:
https://bugzilla.mozilla.org/show_bug.cgi?id=1447237
This has been fixed in later versions. I don't recommend overriding the compatibility since I set the last supported version to the newest version I tested the add-on with. Override it at your own risk :).
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