Fixed Sidebar Navigation not working on Firefox/Chrome

For reasons I can’t explain my fixed sidebar navigation doesn’t stay fixed on Firefox and Chrome, although it works just fine on Safari. Moreover, I’m also noticing that my custom cursor is also not working outside of Safari. Can someone please help?


Here is my site Read-Only: https://preview.webflow.com/preview/austins-first-project-ac674d?utm_medium=preview_link&utm_source=dashboard&utm_content=austins-first-project-ac674d&preview=781973db8738973e90c4e2fbad78adfc&mode=preview