The member will be de-authorized and completely removed from the list. It’s a little more permanent than hiding.
Recover a Deleted Member
You've deleted a member from your network, possibly by accident, and you want to get it back.
Go to the Settings section of the network
Find the Manually Add Member section
Paste in the Node ID
If you’ve lost Node ID, it can be viewed on the device -in the ZeroTier app.
If you don’t see the Delete and Hide Buttons