Meta MUST be kidding...
I have my own app to capture video from a USB camera, and it works 100% perfect, flawless and with every feature I wanted.
But then Meta decided, at some point, that only Meta Quest HDMI Link is authorized to access external USB cameras. No other apps can access external USB cameras (or anything else, iirc).
The problem is that their Meta Quest HDMI Link is BUGGY, it only works "properly" the first time I run it. The second time, the video is a small rectangle at top left, and there is no way to fix that -- only closing, removing permissions, then opening again and reconfiguring.
I don't know how to express my ... well ... without using unproper words.
