@sia It would be great if you could open a bug on bugs.webkit.org as an enhancement request on things you have noticed that identifies these bottlenecks and why they are hard to measure or identify. Also if some of these, you know exactly the code which creates them but you do not why this is happening, opening separate bugs for them is always super useful. Even more so if you have a measure for the same code on Firefox/Chrome Android. Thanks. @jensimmons