[eueueu]

I'd bet using setTimeout with a 0ms delay every loop wouldn't slow the example down significantly, and would have the desired effect of making the UI responsive.

[wging]

You might be surprised. There are conditions under which browsers will impose a 4ms minimum delay when you ask for less. I believe it's when you set a timeout within a timeout.

Edit: close. https://html.spec.whatwg.org/multipage/webappapis.html#timer...

"Timers can be nested; after five such nested timers, however, the interval is forced to be at least four milliseconds."