I've found that you can also refresh the page until YouTube knows you're just wasting their bandwidth and gives up serving ads for a while, or open the video in

I've found that you can also refresh the page until YouTube knows you're just wasting their bandwidth and gives up serving ads for a while, or open the video in Incognito mode where it seems to give you a grace period. For extra fun, install one browser with Adblock Plus (with acceptable ads disabled) and one with uBlock Origin and swap between them as needed.