Bitcoin advocates, led by Jack Dorsey, are urging the messaging app Signal to incorporate Bitcoin payments through a campaign titled 'Bitcoin for Signal.' The initiative proposes using the Cashu protocol to facilitate in-app Bitcoin transactions. Dorsey publicly endorsed the campaign on X, highlighting the potential for Bitcoin to enhance Signal's payment options. Bitcoin developer Peter Todd also supports the move, suggesting Bitcoin could serve as an alternative or complement to Signal's existing MobileCoin payment system.