[jrochkind1]

Much of this discussion is missing that the point is to _speed up_ page load/display. It is NOT like a compiler generating sleeps.

The bazillion tracking scripts loaded by pages is slowing down time to view/interaction on the page. Firefox is taking scripts that are _already_ being marked as loadable asynchronously/delayed, and delaying them until the page is otherwise loaded. That's it. It's not an arbitrary 'sleep', it's an attempt to prioritize UI responsiveness over tracking scripts.

To the extent it breaks or _slows down_ pages, that's an undesired side effect, not the goal. If it does that to a lot of pages, the feature won't be succesful and will be rolled back, I bet.