Minecraft Launcher overload in background

I have a weird problem

Usually after the launcher starts minecraft, the Launcher will shut itself down, but I find that the launcher will run in the background after i update my minecraft Launcher yesterday.

causing CPU overload.

 

After loading a Minecraft 1.14.4 :

CPU of minecraft launcher : 91~98％

 

Processor : 2.2 GHz Intel Core i7 : Intel® Core™ i7-8750H

Memory : 16GB

Graphic Card :

Intel UHD Graphic 630 1536MB
Radeon Pro 555X 4GB

Mac Version : macOS Mojave (10.14.5)