Dong Hualin worked on improving the reliability and maintainability of the delayed shutdown process in the linuxdeepin/dde-session-shell repository. By removing the waitForAppPreparing dependency and decoupling the shutdown logic from system configuration, Dong streamlined the shutdown sequence, reducing the risk of edge-case failures and simplifying deployment across different environments. The work involved refactoring C++ code within the Qt Framework, focusing on system programming principles to ensure a more robust and testable code path. Although the scope was limited to a single bug fix, the changes addressed a core stability issue and contributed to easier long-term maintenance of the shutdown functionality.