I am using VIVE Wave XR Plugin v1.0.1 (released Nov 13, 2020) based off of the Wave Runtime version 3.2.0. The source files are only located in the Library/PackageCache folder when imported from the Vive registry.
The full steps to get it to work per your workaround are:
1) Install the Vive Wave XR Plugin from the Vive Registry.
2) Move the Library/PackageCache/com.htc.upm.wave.xrsdk@1.0.1 folder to Packages/com.htc.upm.wave.xrsdk@1.0.1.
3) Make these edits to Packages/com.htc.upm.wave.xrsdk@1.0.1/Editor/WaveXRPlayerSettingsConfigDialog.cs
public static string[] GetVirtualRealitySDKs(BuildTargetGroup group)
{
return null;// PlayerSettings.GetVirtualRealitySDKs(group);
}
public static void SetVirtualRealitySDKs(BuildTargetGroup group, string[] devices)
{
//PlayerSettings.SetVirtualRealitySDKs(group, devices);
}