Backend changes don't update to frontend, drop-down header menus broken

Hi All! Long time - and that’s a great thing! I need some help from the gurus, now, though.

With recent updates to the latest theme and WP versions, I have a years-old Pro site whose simple inline header drop-down menus stopped dropping down and back-end content changes that show up on a tab in a logged-in browser rarely make it to the public frontend. I get speculationrules errors that research says contains js code that is stopping json drop-down execution but I can’t find it.

I read your Navigation Dropdown Issues post and made the checks but still nothing. Scrolling is turned off on all four page sizes, and I deleted and tested what little global js and css there is, disabled all of the plugins, cleared opcache with Docket, changed from Child to Pro, and even reloaded WP core files. I added remove_action( ‘wp_footer’, ‘plsr_print_speculation_rules’ ); to functions.php. Now I’m calling in the experts. I’ll set up an admin account for you and post a secure note.

Many thanks.