Greasy Fork is available in English.
Some fixes for Youtube polymer engine
< Opinie na Youtube polymer engine fixes
Does it have a history mode where it highlights in blue or grays out videos that you've watched?
Used this extension in parallel with 7kt. I don't like the logo, the menu icons and its size in it, there are no gray previews :(
Hey! There is official plain old youtube script with auto update "https://openuserjs.org/scripts/7kt_swe/Plain_old_youtube_(2020)_7KT_EDITION"
Yes, it's alive
I know y'all are upset that he had to change it, but if you really need the old layout you can get the YouTube Redux extension. It's got such good settings and options that I ditched this script for it like a week ago.
Chrome:
https://chrome.google.com/webstore/detail/youtube-redux/mdgdgieddpndgjlmeblhjgljejejkikf
FireFox:
https://addons.mozilla.org/en-US/firefox/addon/youtube-redux/?utm_source=addons.mozilla.org&utm_medium=referral&utm_content=search