I can't believe adblocker actually works; that youtube doesn't have a way to merge the ads with the actual video, but there you have it, they do work. Watching youtube without adblocker is impossible. Youtube is barely usable as it is with its fvcking bullsh*t crappy slow bandwidth, especially during peak hours.
Embedded youtube videos stopped loading for me with adblock. They wouldn't load at all, as in I couldn't even click the little youtube icon to go to the youtube page for the video. Just a black box appeared where the video should be. I had to whitelist youtube.com for the videos to play.
Just blocked it again based on people in this thread stating it hasn't been causing them issues (and those 30 second unskippable ads have become rather annoying). Hopefully embedded videos continue to work.
Maybe it was just something those sites were/are doing that blocked the youtube video from loading.