SN DM = go to your SN wallet. Select LN address - type my address, put any amount higher than 1 sat and add a comment. That is a SN DM. OFC is read by k00b and ek
But who cares?
TIL you can pay 1 sat to send someone a private comment calling them a *******
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welcome to the SN world sir...
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You can also think of this "method" of "laundering" sats through SN..... Just imagine Pablo Escobar finding this trick...