This happens on pretty much all the sites I've tested with Lenis with elements that are position: fixed. The most common use for this is headers/navs and we're seeing the issue on one of our sites that we're testing Lenis out on.

Here is a recording of the issue.

(Excuse the phone recording, it's difficult to see when using the built-in Mac screen recorder for some reason)

And here are the specs for a couple of the machines we've tested this on:

Are you aware of any workarounds? We'd love to get Lenis on this project and this is the only thing blocking that.