Thank you for posting this, the comments made me want to try and get the ad blockers to work again instead of copying and pasting into a private browser. I've been stuck doing that for several weeks now and it's very tedious.

And you know what? I got it to work, at least for now!

Here's what my issue was: I was using too many adblockers at once. So I turned off everything but Ublocker and Sponserblock, and cleared Ublocker's cache before updating it as another user recommended. It looks like it's back to normal now! And yes, I'm using Firefox.

Hopefully that helps someone with similar issues.