URP Black Screen on Full-Screen toggle: Lenovo 300e Yoga Chromebook Gen 4

Unity Engine
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1

I’m not sure if this is a bug related to Unity or the device. But we have hundreds of clients who are purchasing this new Lenovo Chromebook and there is an issue with URP WegGL builds where the screen goes black when it’s toggled to full-screen. Or back from full-screen. Once triggered, we can’t find any way of getting rid of it. It’s not an issue with Built-In Render Pipeline.

Here is a super basic sample test scene that shows the problem (but again, only these certain Chromebooks):

https://edtechgames.com/tmp2/blacktest/

  • Currently testing on build 2022.3.45f1.
  • If you toggle full-screen right while the logo is still playing it can go to full-screen. But if you ever toggle it back, it turns black and stays that way.
  • If we switch to built-in render pipeline, the screen does not turn black.
  • No other device seems to have this issue (but we still need a workaround for the hundreds and thousands of these particular devices in use.)
  • Device is updated to Chrome 127.0.6613.118. Other Chromebooks with this same version do not have the problem.
  • We get some error message, but we get the same errors on devices that don’t have any problems.

INVALID_OPERATION: drawBuffers: BACK or NONE
GL_INVALID_FRAMEBUFFER_OPERATION: Framebuffer is incomplete: No attachments and default size is zero.
Performance Warning: Recreating Offscreen FB0

Any ideas on what we might be able to change or turn on/off to get this working?

3

We’ve had something similar reported on a Samsung Galaxy S10+ on 2022.3.30 with a game using URP (although without full screen). Trying to dig further into this indicates it may be something to do with devices with Mali GPU’s, although we have someone with a Galaxy S23+ with a newer Mali GPU not experiencing this issue.

I found some of these reports too which sound similar to what you’re experiencing, sounds like if you’re using Linear Colour Space then changing it to Gamma might work however the visual quality may change:

4

Aha, that’s super helpful. Switching to “Gamma” does indeed solve the problem.

We have a lot of effects that need Linear, so I’m not sure if that’s a very workable solution for us, but at least we know a brute force solution now.

And hopefully they take that bug seriously soon:)

Thank you so much for connecting me to those!