Twitter's head of brand safety and ad quality to leave -source

FILE PHOTO: The Twitter logo is displayed on a screen on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., September 28, 2016. REUTERS/Brendan McDermid/

(Reuters) - Twitter's head of brand safety and ad quality, A.J. Brown, has decided to leave the company, according to a source familiar with the matter on Friday, the second safety leader to depart in a matter of days.

The latest departure adds to a growing challenge for new Twitter CEO Linda Yaccarino, even before she steps into the role.