Disable scroll animation when full size menu is open

So I am currently struggling with keeping my full sized menu completely in the viewport albeit it being position fixed. I understand the problem, as I have animations moving the Navbar (in which the full size menu is contained inside) out of the viewport, however I am not really finding a proper solution for this. My best guess would be to

I have tried my own custom javascript, but adding overflow: hidden to the body doesn’t help. Neither does stopping eventPropagation when my full sized menu is shown.:

Also, finsweet no scroll attributes also don’t work in my case:

Any solutions to this problem I am facing?

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