When users install proxy browsers or Tor, they expect absolute privacy while navigating the web. However, one developer has discovered that three separate data leaks can occur while using WebKit browsers on iOS or macOS. According to the Mysk blog, DNS prefetching, WebAuthn for Passkeys, and WebTransport can all reveal data about the user in spite of proxy use or iCloud Private Relay. Tor browsers, proxy apps, and Safari are affected, but VPNs are not since they're acting at a system level to encrypt all traffic. The leaks were discovered after a Psylo user reported a DNS leak and the investigation uncovered all three problems.