I noticed that when I call
listunspent on Bitcoin Core, UTXO with 0 confirmation are labeled
unsafe, and thus prevented from being spent with
fundrawtransaction. As soon as there's one confirmation the tx is
safe and I can spend it.
Being able to modify the target for a tx to be considered
safe, for example set it to 3 or 6 confirmations instead of just 1, would make my life easier, but I can't find an option for it. Is there some way to do it?