David is a user on mstdn.io. You can follow them or interact with them if you have an account anywhere in the fediverse.
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@fdavidcl does it use the number of connected instances?
@angristan Nope, it's finding individual connections between instances by counting users from one instance following those from another (only a small sample of users though, the fediverse is too big for that)
@fdavidcl oh interesting