Mozilla announced a few months ago they were working on Tab Groups, Vertical Tabs, Profile Management. I don't know if it's related but seemed to coincide with

Mozilla announced a few months ago they were working on Tab Groups, Vertical Tabs, Profile Management. I don't know if it's related but seemed to coincide with getting a new CEO. https://connect.mozilla.org/t5/discussions/here-s-what-we-re-working-on-in-firefox/td-p/57694 https://connect.mozilla.org/t5/discussions/here-s-what-we-re...