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Disable YouTube video & screen based ads at home page, and right before or in the middle of the main video playback. Also disable YouTube's anti-adblocker popup dialog. For new YouTube layout (Polymer) only.
< Feedback em Disable YouTube Video Ads
YouTube is transitioning to a server based ads, and is already experimenting with it at random time and at random videos. So eventually, no script will work. Though for now, the server based ads is not applied globally yet.
This worked for a couple of months, but then YouTube started not playing the videos at all if there wasn't an ad able to be played. It's good for short-term use, but YouTube caught on to it and 'fixed' it