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"I tried downloading and launching the sample app on Unity 2020.3.21f but it crashed and opened the app on Safe mode."
Please click "Ignore " to enter the project, and then open Build Setting for switching the Platform to the UWP, after doing this, the compilation errors will be solved.
"How do I go about adding Scene understanding to my Unity projects? "
It is recommended to import SceneUnderstanding SDK packages via the Mixed Reality Feature Tool. For more information please see: Where do I get the SDK?
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