At least one extension maintainer (yappy, a pushbullet alternative) says that they are unable to sign their extension because of the 3rd party library they use, so while they have both firefox and chrome extensions, only the chrome one works.
That would be very disappointing from mozilla! I only found a
support-thread from yappy in 2016 but if this is still up-to-date there
should be an outrage on HN's frontpage.
I also made a simple, private(!) extension before I learned about the
signing-requirement and that it won't work without uploading it. So I
canceled my career as an extension-writer and just went to bed angry.
They really fucked this up (without even mentioning the "armag-addon").
