I've been hitting exactly the same problem on Debian 8 running Firefox 49.0-5~bpo80+1 from https://mozilla.debian.net/. The issue seems to be solved in Firefox 50.0~b11-1~bpo80+1.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1628014 Title: WebExtension fails to install only on ubuntu packaged firefox To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1628014/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
