Thanks for asking.
Many stuff is disabled by default, but it’s a moving target. There are some tutorials online to read.
It depends on what the browser is used for. Some hardening breaks certain sites.
Some stuff to look at:
- dns-prefetch - geo - cookie - dom (disable, breaks sites) - browser.cache.disk - clipboard.events - media.peerconnection - healthreport - spoofRefererHeader
Chrome doesn’t remove history when closed is a big issue.