Some more resources to learn more:

• Payjoin for More Than Privacy - Interactive Payment Batching
• Payjoin.org
• https://payjoindevkit.org/blog/pdk-an-sdk-for-payjoin-transactions/
• Setting up BTCPay Server's Payjoin feature
• Design Guide - The Payjoin experience
• How To Open Multiple Lightning Channels At Once
• Human Rights Foundation - Donate to Payjoin project