Quantum exposed: this address has revealed its public key in a prior spend. A sufficiently powerful quantum computer could derive the private key.
pubkey 048c6421f94193e54299a5b1749d765a56d5714204950643c0b657fc220409d2fb68af50b85b2f22168f4016d97dad72f95977cac2a55933b726cd9e31c0c14d83