overflow-{x,y} on Tizen causes major slowdowns

[JeWe37]

Describe the bug
Any use of overflow-{x,y} causes major slowdowns when scrolling on Tizen. It is used solely in header_transparent.css. I'm hardly an expert on CSS and removing it produced no visual differences that I could notice, perhaps it might make sense to just remove it entirely? The only media query I found that let me reliably distinguish my TV was pointer: none.

To Reproduce
Use

@import url('https://cdn.jsdelivr.net/gh/CTalvio/Ultrachromic/base.css');
@import url('https://cdn.jsdelivr.net/gh/CTalvio/Ultrachromic/accentlist.css');
@import url('https://cdn.jsdelivr.net/gh/CTalvio/Ultrachromic/header/header_transparent.css');

on a Samsung TV.

Screenshots
If I could add a video I could show you major stuttering while scrolling.

[JeWe37]

Duplicate of #38 . Potentially the pointer: none could be useful though to others.