Greasy Fork

The script works great. But it does not work very well with this script https://greasyfork.org/en/scripts/34388-space-efficient-youtube

There's no way I can account for all the modifications that can exist...

I get you.

You can customize the positions using an additional script:

// ==UserScript==
// @name           YT: not interested in one click CSS
// @match          https://www.youtube.com/*
// @grant          GM.addStyle
// @noframes
// ==/UserScript==

GM.addStyle(`
.yt-one-click-dismiss:not(#foo) {
  right: 36px !important;
}
.yt-one-click-dismiss[data-block]:not(#foo) {
  top: 10px !important;
}
.yt-one-click-dismiss[data-block="channel"]:not(#foo) {
  top: 40px !important;
}
`);

If you use Stylus or Stylish or a similar extension:

@-moz-document domain("www.youtube.com") {
.yt-one-click-dismiss {
  right: 36px !important;
}
.yt-one-click-dismiss[data-block] {
  top: 10px !important;
}
.yt-one-click-dismiss[data-block="channel"] {
  top: 40px !important;
}
}