layout is suspended automatically. Unless you query the dom for something, in which case you can get lots of thrashing. For example, you don’t want to add some dom elements, then get their height/width as that will force the layout. And don’t do that in a loop! Last I looked, addjng/removing dom elements only schedules the layout and repaint. Things have gotten more multithreaded since I looked at browser code for this, but I doubt they would make a performance regression here.
