Climate activist Greta Thunberg was filmed giggling as she declared “f–k Germany” and “f–k Israel” at an anti-Israel rally in Germany Friday, video shows. The 21-year-old appeared as a speaker at the demonstration in the southwestern German city of Mannheim, which included a discussion focused on “solidarity with Palestine and the climate movement.” “F–k Germany,” Thunberg says in the clip, before bursting into laughter. “And f–k Israel,” she adds to rapturous applause and whistling from the crowd. A city spokesperson told German news agency Deutsche Presse-Agentur that 700 protesters attended the rally, which they described as peaceful. Thunberg, however, has...