What add-on are you talking about? Please provide its link.

Have you contacted its support?

cje24576 said

I'm trying to find an add-on that will show the "Watched" badge on Youtube. I was using a Mac computer & I had an add-on there that worked. I just started using my new Windows 10 computer, I installed the same add-on I had on the Mac, but it doesn't work on the new computer. Can anyone help? Does anyone know of any add-ons that will work?

This is the add-on I'm talking about: https://userstyles.org/styles/135325/youtube-watched-badge I added it to the new Windows 10 computer, but for some reason it's not working.

FredMcD said

Have you contacted its support?

i have contacted support, but no response. I was wondering if anyone knew of an add-on that would do the same thing?

cje24576 said

This is the add-on I'm talking about: https://userstyles.org/styles/135325/youtube-watched-badge I added it to the new Windows 10 computer, but for some reason it's not working.

It works by changing the red progress bar to an overlay. But I don't see any red progress bars below video thumbnails. Do you see them? Do they only appear when you are logged in to your Google account??