I think they want to encourage wider adoption of the Beta version, so they treat it similarly to the Release. The logic seems pretty questionable to me though.

I think they want to encourage wider adoption of the Beta version, so they treat it similarly to the Release. The logic seems pretty questionable to me though. If you can install a Beta version of Firefox, you should be able to avoid consenting to allow malware to run on your computer (this change is primarily targeted at extensions installed by some user action -- like something silently side-loaded by an application installer).