The core goal of deepin 20.9 is to provide users with a stable system. This version does not integrate new system functions, it mainly focuses on fixing and optimizing stability issues present in the 20.8 version, in order to ensure system stability. Additions and optimizations: upgraded Qt to version 5.15.8; optimization of the height of the window tube title bar from 40 pixels to 24 pixels; updated system log viewer application; updated system photo album application; updated system drawing board application; updated system software package management application; supported devices with a boot partition and undamaged terminals to automatically repair the root file system in case of damage during the boot process; updated log collection tool; updated software package installer; updated terminal application; optimized the high-performance mode/balance mode strategy.