"Basically, the background here is the FBI, I think, basically came to us- some folks on our team and was like, 'Hey, just so you know, like, you should be on high alert…  We thought that there was a lot of Russian propaganda in the 2016 election. We have it on notice that, basically, there's about to be some kind of dump of that's similar to that. So just be vigilant," Zuckerberg told Rogan.