Worked on the jxxghp/MoviePilot repository to enhance the reliability of Windows push notifications by addressing a persistent 400 Bad Request error affecting WNS endpoints. The solution involved backend development in Python, introducing a helper to inject the required X-WNS-Cache-Policy header and implementing a default TTL policy for Windows notifications. Comprehensive unit tests were added to validate the new logic and ensure existing functionality remained stable, with a focus on robust testing practices. This targeted fix reduced notification delivery failures for Windows users and improved the overall dependability of web push services, emphasizing careful attention to backend and webpush integration.