[jacquesm]

The correct way to deal with that problem is to decouple the UI from the computation, once process for each would be the ideal, anything less is going to messy and require all kinds of hacks to give the same outward appearance. Better still: one supervisor process and one for UI and computation each.

[skybrian]

Well, in a web app you don't get to make those choices, but you could use a web worker.