German Chancellor Angela Merkel shared a picture on her official Instagram account that shows her staring down President Donald Trump during the G-7 Summit in Canada this weekend. True to form, online commenters have since turned the photo into a humorous caption contest. Merkel—or an aide that runs her account—shared the picture on Saturday, as Trump was preparing to depart early from the meeting in Montréal, Quebec ahead of a high-stakes Singapore meeting with North Korean leader Kim Jong-un. The photo depicts Trump sitting behind a table with his arms crossed, while stony-faced aides and leaders look in his direction....