MOSCOW (Reuters) - Russia said on Wednesday it had blocked the Swiss email service ProtonMail, popular among journalists and activists for its focus on user privacy and high level of encryption.Russian communications watchdog Roskomnadzor said ProtonMail, which uses end-to-end encryption to protect user data, had been used to send fake, anonymous bomb threats.Such threats have frequently led to mass evacuations of public buildings across Russia. Roskomnadzor said that ProtonMail had refused to..