Since we can’t hope to focus if we spread too thin, let alone offer something uniform if we’re not keeping parity with mainstream, WebExtension support should be removed from UXP. Our platform will focus more tightly on everything XUL, including extension technologies which are effectively now our own after Mozilla abandoned it.
This is a meta issue to remove it from all components.
Please create separate issues for individual components and make them block this meta bug.
Plan of action:
@mattatobin assigning you to this since you probably have the best grasp on how to give this shape.
(P.S.: I hold you to your promise to never complain about Jetpack again when WE support is removed ;) )