[lxt]

This is kind of what we have in mind.

The model is that we want to make Firefox itself more webby in the way it ships. Features should be independently updatable from the core browser, and we should be able to do phased rollouts to help us watch for issues, control for load, and so on.

We are looking at offering very experimental stuff in a purely opt-in process, and updates to regular features as if they were third party add-ons (with some twists in how they have to be implemented).