UTXO probing attack using payjoin

The discussion emphasizes the complexities and considerations surrounding the implementation and use of payjoin transactions. It is highlighted that payjoin requires additional information from the recipient, which can raise privacy concerns. However, it's argued that these concerns can be mitigated through user education on the trade-offs involved, the implementation of necessary features in wallets, and due diligence in executing each payjoin transaction. These steps do not entail extra fees beyond those already incorporated into payjoin transactions, suggesting that the barriers to adoption might be more about understanding and operationalizing these practices rather than cost.

The dialogue also points out issues with both the implementation and the protocol of two-party payjoin transactions. This demonstrates a broader concern within the cryptocurrency ecosystem about balancing user privacy with the technical challenges of adopting new transaction methods. The mention of an attempt to use payjoin with a specific setup involving testnet.demo.btcpayserver.org and bullbitcoin wallet, which was unsuccessful due to errors, further illustrates the practical difficulties users may encounter when trying to utilize these advanced features. This anecdote serves as a real-world example of the hurdles that must be overcome to make such technologies accessible and functional for the wider community.