[Feature] Helper visualization when your virtual screen is fully "offscreen".

[ikogan]

It's possible to get into a situation where your virtual display is fully "offscreen" in space. Since this just renders "nothing" in the glasses, it feels like something is just broken. It would be helpful to have some sort of indicator that you do indeed have a floating screen, it's just elsewhere in space. Some ideas might be:

• Lighting up the edge of the screen that is in the direction of the virtual screen.
• Drawing a symbol in the middle of the viewport.