I had whitelisted CNN.com on the Adblock Plus app, but the videos and their unskippable, long pre roll ads refused to play. Had to watch on the CNN app all year, but sometimes it was damned inconvenient.
Tonight, I disabled Adblock Plus, played a video (with ad) on CNN.com, re-enabled ABP, made sure CNN.com was on the whitelist, and now the videos and damn ads play like they should. It just needed an app restart, I guess.
Add a website to the whitelist | Adblock Plus
Add websites that you trust and want to support to your Adblock Plus whitelist. Ads will be shown on these websites.
— Read on help.eyeo.com/adblockplus/add-a-website-to-the-whitelist