Windows Authentication: fail to get User.Identity.Name in controller (always null)

 Project was generated by yo `aspnetcore-spa - React With Redux`, with following settings

launchSettings.json
```
    "windowsAuthentication": true,
    "anonymousAuthentication": true,
```
Symptom
 User.Identity.Name; is always null in any controllers

Walk around
Set anonymousAuthentication to false can walk around it, but just curious why.