Impact and defense tips
https://www.bleepingcomputer.com/news/security/new-ileakage-attack-steals-emails-passwords-from-apple-safari/
Academic researchers created a new speculative side-channel attack they named iLeakage that works on all recent Apple devices and can extract sensitive information from the Safari web browser.
iLeakage is the first demonstration of a speculative execution attack against Apple Silicon CPUs and the Safari browser. It can be used to retrieve with "near perfect accuracy" data from Safari, as well as Firefox, Tor, and Edge on iOS.