Sen. Marsha Blackburn, R-Tenn., and Sen. Richard Blumenthal, D-Conn., have sent a letter to Meta CEO Mark Zuckerberg, asking that Instagram's new map feature be taken down due to privacy concerns. NBC News' technology contributor Joanna Stern explains how the feature works and why the senators say Meta is not doing enough to protect children online. For more context and news coverage of the most important stories of our day, click here: nbcnews.com » Subscribe to NBC News: nbcnews.to/SubscribeToNBC » Watch more NBC video: bit.ly/MoreNBCNews NBC News Digital is a collection of innovative and powerful news brands that deliver compelling, diverse and engaging news stories. NBC News Digital features NBCNews.com, MSNBC.com, TODAY.com, Nightly News, Meet the Press, Dateline, and the existing apps and digital extensions of these respective properties. We deliver the best in breaking news, live video coverage, original journalism and segments from your favorite NB...