So I recently upgraded to version 3.x (it’s overall great!) and have been running into this issue with intermittent high Cumulative Layout Shift on mobile. You can even sometimes see it when you load the site on the phone:
Yes, I’ve been messing around with WP-Rocket… Looks like the CLS is taken care of, but now the site is slower… Oh well, I’ll dig at it. Thanks for getting back to me, though. π