It does not. The fingerprint always only unlocks the device's HSM ("secure enclave" in Apple speak).
Between your devices enrolled in the ecosystem, private keys are synced securely (AFAIK, they make it so that an existing device’s HSM encrypts keys using the pubkey of the new one’s HSM); for signing up using your device on someone else's computer there's a process that combines QR codes with Bluetooth communication.
IIUC Apple syncs them using the most secure way they can, i.e. when you enroll a new device to your account the existing device, the existing device's HSM encrypts keys using the pubkey of the new one's HSM; and for recovery from being left with 0 Apple devices there might be (?) an escrow option that's optional (?)
I preordered it on Steam and played on a big PC as soon as possible, it looked incredible to me, the initial release did crash occasionally but I always found it strange how much attention that instability got compared to how Todd Howard games are just casually permitted to be comically buggy.
Back in the day on the other place it was a very good community. Way back in the day. Before the quarantine and takeover and whatever the hell else happened since…
There's no need to access the full file system to download to wherever the user wants. In fact the user might not want to use the local file system, but instead a "cloud" storage provider app!
??? Channels are literally public by definition and viewable even without an account. That's the whole point of channels. They're more like blogs than messages.
Moved most of my stuff there a while ago, has been pretty great.