pendingBalance property
Value of the wallet's unspent UTXOs that are not spendable yet: the network is not known to hold the transaction that pays them, or it held it and a reorganization took the proof away. The wallet's own money, and not part of totalBalance — the same treatment as watchOnlyBalance and reservedBalance, which are also the wallet's and also unspendable (bead libspiffy-z84j).
It was reported nowhere before, so an application saw it as zero: at
its worst, a payment that confirmed and then lost its block to a
reorganization read as money gone, for as long as it took a fresh proof
to arrive. TransactionConfirmationRevertedEvent says when that
happens and this says what it is worth.
These outputs cannot be selected for spending, by design: an output whose proof left the active chain cannot be put in a BEEF anyone can verify (bead libspiffy-0lx). The wallet's own write model and the read model's wallet row count them as unconfirmed instead; this API reports them apart so that neither number claims the money can be spent.
Implementation
final BigInt pendingBalance;