I’m fairly sure the JS standard guarantees that no layouting (or any form of rendering) would happen mid function execution. Haven’t looked in the source code y

I’m fairly sure the JS standard guarantees that no layouting (or any form of rendering) would happen mid function execution. Haven’t looked in the source code yet, but if they do function updateAllClocks() { A.innerHTML = ...; B.innerHTML = ...; } Then A and B would update on the screen on the same frame and the order doesn’t matter (If A is not parent of B or vice versa of course) This is not true if they do a lot of setTimeouts(), but is true for all other “normal” synchronous code.