Ubuntu interface problem

after using the normal shutdown yesterday, my younger brother"s ubuntu restarted to enter the interface and found that the top status bar disappeared, the left menu bar of the system also disappeared, and the menu bar of the program also disappeared after opening the program, so Baidu search found that someone had the same problem as me. So follow the post:
https://blog.csdn.net/terence.
enters ccsm and finds that my Ubuntu Unity plugin is really not activated (no hotkeys are occupied), and there is still no response after exiting and restarting according to the post operation. Use:
dconf reset- f / org/compiz/
unity-reset-icons & disown
will briefly appear in the top bar, and then disappear
restart unity will not respond.
get down on your knees and beg for guidance
I"m pretending to be Cairo-Dock.

Mar.02,2021
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