EghtesadOnline: On Oct. 19, as the third and final presidential debate gets going in Las Vegas, Donald Trump’s Facebook and Twitter feeds are being manned by Brad Parscale , a San Antonio marketing entrepreneur, whose buzz cut and long narrow beard make him look like a mixed martial arts fighter. His Trump tie has been paired with a dark Zegna suit. A lapel pin issued by the Secret Service signals his status. He’s equipped with a dashboard of 400 prewritten Trump tweets. “Command center,” he says, nodding at his laptop.

EghtesadOnline: Facebook Inc.’s platform was a crucial messaging tool for President Donald Trump’s 2016 campaign, according to the campaign’s digital director -- who told CBS’s “60 Minutes” that he hand-picked pro-Trump “embeds” from the company to help him use the platform in targeted ways.