Yann: Ah! Thank you so much! It probably would've taken me ages to figure out that I had put Scroll To behaviour on the menu by accident. That is fantastic, you have no idea how happy that makes me. I had made a number of similar changes to my project after linking it here, but I shall go through and see what else is changed from your version.
I doubt I'll ever forget this "lesson" now that it's solved.
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