Test coins are weird: some of them are
free, some of them are
burned.
Both the "free" and the "burned" link to the same transaction. I get that the coinbase reward is burned, because it is sent to OP_RETURN, but where are the free coins?
Of course, for CPU-based mining, some modifications are needed, but I think grinding coins with bitcoin-util should still be possible. I will think about some kind of such implementation.
What's the recommended way to mine testnet4 with CPU? Is it possible directly from Core with generatetoaddress? And, is there mining software for testnet that is configurable with GPUs?