When attempting to bump a BIP125-enabled transaction fee via RBF using the GUI, the increase transaction operation fails.
Two scenarios can cause this to occur:
- No change address in original transaction
- Insufficient change available in original transaction
Both scenarios can be addressed by adding additional inputs to the transaction to satisfy BIP125 requirements for increase.
These screenshots illustrate the flow.
- Transaction sent with RBF flag enabled
- Context menu for the transaction shows "Increase Fee" enabled
- Error Dialog for "Increasing transaction fee failed"
A similar error dialog occurs when there is insufficient change when increasing the transaction fee.
A more advanced scenario for fee bumping would be if coin control is enabled as described here: #14724 (comment) I think there is value in addressing the automatic coin selection scenario even if punting on fee bumping w/ coin control is punted on.