SIGMA on Nostr: What client is that?

{ "id": "57989fbf396a45f6afb1cf9a5cbddf0d40af44182b85a98c28aa76d882ccb7e2", "pubkey": "2225102884ffa05645821e13ce6cca8c7951ceb6a07ab1a6f7b63250a9217cfb", "created_at": 1673169570, "kind": 1, "tags": [ [ "e", "850dcbda80d57b711df88ebdf0656e27e16215ad33953aa466a2ab573f4152cc" ], [ "p", "4523be58d395b1b196a9b8c82b038b6895cb02b683d0c253a955068dba1facd0" ], [ "p", "97934b0d22be7a044b8c7dc08a848938671d1247502796a34667745bb0491ac2" ] ], "content": "What client is that?", "sig": "0e4f0a4b156e4e2eb0c4a194f6f143423785d26b60d932f117f37597c54ca30edfab395ff9357c477ca5e59a2492bf4d64027e775f93c86d03b20ee4c0812f9d" }