[kibwen]

> That's what I've been afraid of. When epochs were announced, I thought it is kinda nice to have backwards compatibility while introducing breaking changes.

That is what editions are, though (though as I keep insufferably emphasizing, all breakage is opt-in). Can you be more specific about what you're afraid of?

> Firefox Quantum doesn't involve much of breaking changes (if you don't consider deprecating the old plugins one, that is).

You must not have been on any web forum discussing Firefox 57 if you don't remember the cacophonous, world-ending drama that deprecating legacy add-ons created. :P