This article about Facebook’s auction system, which Brad Parscale just endorsed, says that Facebook systematically charged the Clinton campaign more for ad space than the Trump campaign because Clinton’s ads were less “provocative.” wired.com/story/how-trum… 
The article is written by an insider on Facebook’s monetization team, so presumably it’s accurate that Facebook charged Clinton more than Trump for the exact same ad real estate. In so doing, they effectively subsidized an absolutely hideous campaign of racial provocation.
Imagine we found out a local Fox tv station in a swing state was selling ads to opposing campaigns at different rates based on some black-box determination of how interesting they thought the ad’s content was, and the Democrat reliably got charged 5x more than the Republican.
Reverse it: let’s say a radio station in the Pittsburgh market decided to price political ads based on how “responsible” it determined the ad content to be, and accordingly Clinton paid $7,000 for 30s while Trump paid $100,000. Wouldn’t that seem like a big campaign contribution?
