In-protocol liquidity probing and channel jamming mitigation

A recent proposal suggests using probe requests without HTLCs to reduce load on nodes, improve user experience, and avoid locking up liquidity. However, there are concerns about forwarding nodes exploiting this by performing channel-jamming attacks or disrupting onion responses. To mitigate these potential attacks, the proposal suggests adding a message that indicates when a previous hop lied about its capacity. The sender would still have control over their funds in the channel, so they should be able to determine if they have capacity or not. The author of the proposal encourages others to contribute to the development of the new messages for the Lightning Network.