Hello, Welcome to Microsoft Q&A,
For SpectatorView, please using the latest release: Microsoft Mixed Reality Spectator View v1.1.0. For Unity, the latest Unity 2018 LTS (Long Term Support) stream is recommended as the best version to build the SpectatorView app, and the current recommendation is to use 2018.4.36f1: https://unity3d.com/unity/qa/lts-releases
----
If the response is helpful, please click "Accept Answer" and upvote it.
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.