But you’d trust a megacorporation closely tied to government that has an explicit interest in tracking you, keeping paths for intelligence agencies and law enforcement open, and generally being deceptive? You trust browsers that openly phone home about your activity?
I gauge the risk of my government targeting me lower than the risk of hackers stealing/selling my information. Mainly because the latter has occurred to me numerous times already.
If you're really this serious about security, you should be using Qubes OS. Then, a browser choice stops being important, since the strong isolation would prevent an exploit to do any damage. And disposable VMs allow to do insecure staff without any risk.