YouTube is the largest network for sharing 360 videos. However, there had been no YouTube app for VR platforms other than Google Daydream, Google Cardboard, and Playstation VR. But now, YouTube has an app for Steam VR, which is used by HTC Vive, Oculus Rift and Microsoft Mixed Reality.
The app’s listing shows that it is compatible with HTC Vive. It doesn’t mention Oculus Rift and Microsoft Mixed Reality headsets but it should work as well. I’ll try it out later.