Add Position: Sticky to Large Tables

[manngo]

Looking at the article at Key Values - Web APIs | MDN I see some very large tables. Scrolling through these tables inevitably loses the table header.

Since I always use Firefox it was a simple matter for me enter the developer tools and add:

thead {
	position: sticky;
	top: 0;
}

Would it not be possible to add this to the documentation style sheet itself?