>>362460036
Basically, it abuses the stream camera and shader magic to put red blocks/red pixels in the corner of your desktop window's screen. Other programs can then read out your VRChat window and see the pixel colors, and then those programs connect to your toy and control it based on those colors.
If you go to almost any lewd world with "working haptics", you can see the red, black or white blocks in the top left of your desktop screen.
These pixels can show up in someone's avatar preview too, make sure to poke fun at them for it.