I've done something not the same, but a compromise previously using the Window object's `beforeunload` event to fade out everything in the DOM smoothly, and then using the `beforeload` and `load` events to fade the new DOM back in. It's a bit of a halfway between having sliding transitions, etc. You might be able to simulate that even further than I ever tried.

https://developer.mozilla.org/en-US/docs/Web/Events/beforeun...