my bitcoin knots spam/exploit filter settings.

block non-bitcoin txs exploiting the network and the blockchain.

no normal bitcoin user uses OP_RETURN. it might be used by side chains and companies and stuff for timestamping, or proving something happened in some order.

so i only allow the default 42 bytes which is more than enough for a hash.

BUT i also want 50x more fee for OP_RETURN data. so its still cheap for side chains, but if you try to spam bunch of small OP_RETURN(s) to reconstruct later, you gotta pay more.