Okay, I think your reply helped me narrow down what is happening…

Just a theory, but I think the fixed header scrolling issue is only present when I refresh inside a devtools resizeable window.

I’ve attached a video below of me firstly refreshing the page, and seeing that the anchor links work in full-screen. I then toggle the ‘device toolbar’ in devtools and refresh the page – this time the anchor links are broken (with fixed header).

Let me know if you have any insight into what is going on, I’ve spent way too much time chasing my tail for a non-issue (lol). I just tested across multiple browsers and mobile devices myself and it works as expected like you mention (as long as the devtools>device toolbar is not open).

Thanks for your help :)