A Unity ID allows you to buy and/or subscribe to Unity products and services, shop in the Asset Store and participate in the Unity community.
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thx
Finally, I got it. You can follow these steps, that works for me. 1. Update your unity to the newest version, and don't forget to update your HD...
I also try to play with this new feature, but it just didn't work. My version is 2018.1.8