Thank you very much for the note. I use hugo to render the site and don't have any specific setting for back button behavior. I'll check it out.
Edit looks like an issue with “Hush Nag Blocker” (https://apps.apple.com/us/app/hush-nag-blocker/id1544743900) which was originally installed to deal with the cookie nag spam epidemic. I’ll have to look into alternatives.