SimplestBitcoinBook on Nostr: I used to use Brave but got discouraged with their shitcoin thing. Just downloaded it ...

I used to use Brave but got discouraged with their shitcoin thing. Just downloaded it again. Do you know what this (actually) means when they say identifiers/usage data collected but not linked to you?
Also since it’s not fully FOSS, how can one be sure about what they collect, or does the randomized fingerprint cover that issue? (I’m clearly not a coder :)