Videos don't play with "shields" tracking and advertising blocker on

For information, I can confirm.
Methinks you should click that “report broken site” on the shields window.
Two of the blocked trackers are https://www.nu.nl/static/js/organisms/tealium/nu.tealium.recommendations.js?v=3 and https://cmp.nu.nl/wrapperMessagingWithoutDetection.js from that same site, my bets are on those.
Some sites employ anti-ad-blocker techniques, not sure if this is the case or simply their bug.

update: see Can't switch between accounts in YouTube - #9 by fanboynz for a similar problem and temporary workaround – meanwhile I read up on adblock syntax.