KDE Print Manager – Completing CUPS 3.x Support and Printer Application Integration

This project focuses on completing and refining KDE Print Manager’s transition to CUPS 3.x, ensuring full compatibility with the newer printing architecture while still supporting CUPS 2.x. Although core functionality already works, several features—particularly those related to modern, driverless printing—remain incomplete. The shift in CUPS 3.x toward IPP-based print destinations instead of permanent queues requires KDE Print Manager to better handle discovery, grouping, and display of printers such as network devices, IPP-over-USB printers, Printer Applications, and shared remote queues. The interface should clearly reflect the temporary, on-demand nature of these queues. A major aspect of the work involves improving support for Printer Applications, which are replacing traditional PPD-based drivers. The system should prioritize these modern solutions in workflows like “Add Printer,” while still allowing legacy configurations when necessary. Additionally, the user interface needs refinement to clearly distinguish between classic queues, driverless printers, and Printer Applications, and to provide easy access to external configuration tools like web interfaces. Finally, the project emphasizes strengthening test coverage, especially for newer CUPS 3.x features such as IPP destination handling and Printer Applications. By integrating comprehensive unit tests into the CI pipeline, the goal is to ensure long-term stability and reliability as the Linux printing ecosystem continues to evolve.