Is your Virtual Private Network spying on your browser activity? According to a bombshell study by private email provider Proton, many VPNs installed in the U.S. are actually tracking users instead of helping them. Even worse, some of these offenders are registered to companies in China. Here’s what you can do to keep yourself safe.VPNs are meant to encrypt your web traffic so that third parties — like your internet service provider, digital mar…