Question: Finalizing a fully signed PSBT #469
Description
I have the following fully signed (regtest) PSBT
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
and create a dummy_wallet (unrelated to the PSBT inputs):
dummy_wallet.sign(psbt, None) returns False
It fails to finalize the transaction. Comparison: Sparrow can finalize the PSBT to a fully signed tx.
Am I doing something wrong, or why does bdk need the source wallet to finalize the PSBT?