I think they're using BSV

Raw JSON

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  "id": "00000b5be162455b0a2dd7ef2a771ab2314c6bb713599b43d7de542deaed765e",
  "pubkey": "e2ccf7cf20403f3f2a4a55b328f0de3be38558a7d5f33632fdaaefc726c1c8eb",
  "created_at": 1775739576,
  "tags": [
    [
      "e",
      "00006c1a5c39319f3d54b95cd82b39ad966a434dd3a4812cfa6876f8e2679aa5",
      "wss://nostr.mom",
      "root"
    ],
    [
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      "wss://nos.lol",
      "reply"
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    ],
    [
      "client",
      "Wisp"
    ],
    [
      "nonce",
      "9191",
      "16"
    ]
  ],
  "content": "I think they're using BSV",
  "sig": "ab56df8a8f8d7f318db88a7bd722e6aced1265571461000a51e2c1e14d61b06c02e22760b9b7bb973022e230cbe61b8a9ffc9887012b2cbe762d2f31dd87aa4e"
}