Doesn't render background on mobile out of vr in some cases

Description:
A-Frame doesn't seem to render background (whether it's a-sky or cubemap sky, it doesn't matter) when there are no other entities present to render. It happens only on mobile. You can reproduce it in the given URL on mobile device (I use Chrome on mobile). Steps to reproduce:

1. Drag to a view where no boxes are present
2. Enter VR Mode
3. Exit VR Mode

If you exit VR with entities present on screen, everything will render as expected.
If you enter and exit VR when no boxes are present, it will show white screen - no backround. If the screen is white you can drag to a place where entity should be shown, it will finally render everything.
No demos from https://aframe.io/ have this issue since there is always default cursor present on screen.

Temporary fix I use for my demos is very distant, small entitity as a child of camera.

• A-Frame Version:
• Platform / Device:
• Reproducible Code Snippet or URL: private-scent.glitch.me/ (same demo as in https://github.com/aframevr/aframe/issues/3330 - when i don't have AFrame's default cursor, there's nothing to render)

No source file or test is named. Start by opening private-scent.glitch.me in Chrome on a mobile device and reproduce the VR enter/exit sequence with and without visible boxes; done means the background renders after exiting VR in both cases.