Certainly there is no publicly released client software configured for mainnet
The mercury client code can be configured to use mainnet statecoins by simply setting network = "bitcoin" in the client's Settings.toml file, so it's not that hard to set up. In fact, to demonstrate the vulns to mercury I double-spent some mainnet coins after ostensibly "transferring" the statecoin UTXO to Tom. But it would take a conscious effort to do that, in spite of blatant warnings to the contrary.
network = "bitcoin"in the client'sSettings.tomlfile, so it's not that hard to set up. In fact, to demonstrate the vulns to mercury I double-spent some mainnet coins after ostensibly "transferring" the statecoin UTXO to Tom. But it would take a conscious effort to do that, in spite of blatant warnings to the contrary.