@Skyge Thanks for the response.
I understand what the code does - it appends the signer address to call data before forwarding a call to a contract that inherits from ERC2771Context. My question is whether this contract has been audited and is considered safe by OpenZepplin. The comment mentions it is for use in testing, implying that it shouldn’t be used in production, but not clearly stating that. Honestly I’d rather use this MinimalForwarder in production as it’s simpler than the GSN one and I dont require the added typehash registration functionality available there. I would also guess that the MinimalForwarder is cheaper from a gas point of view as it doesn’t make two additional SLOADs per call.
The reasons I ask about whether the MinimalForwarder has been deployed is because these kinds of forwarders are designed to be singletons. More than one per network is not required. Indeed as mentioned by the MinimalForwarder author @Amxx here it is preferable that a single forwarder address is converged upon, although I don’t think the reasons apply for my particular use case.