Hi, thanks for the answer.
Do other Verge3D demos work for you as expected?
What browser/OS are you using?
The demonstration of the city I think it looks good and the one of the cube also, the one of the teapot heater also.
In the example of the metalic cube with the monkey I can see that it is represented correctly but the background is always dark, when it should be gray.
But i have problems with a simple box without texture or material.
Finally, I found out that with the Microsoft Edge browser I have no problems.
But I would not like to use that browser. ;)
When I compare the result in google chrome with microsoft edge it always happens that in the latter it looks brighter.
Attached image comparing both browsers with the teapot demonstration.
I send you what you have asked me using the Chrome browser, the result with Microsoft Edge is the same
I have tried two computers, the first with Windows 7 and the other with Windows 10, the browsers are updated in both and the graphics drivers are also.
And i use the opengl version 3.3.
My graphics cards are not powerful, they are old, 5 years old, maybe there is the problem?
Finally, I have activated the draft extensions in chrome but it does not solve anything
I think the problem is in the representation of the background, in the nightstand tutorial, i can not see the hdr background using chrome, but it is okey using Microsoft Edge. And that should affect the general lighting of the scene.
I hope there is some solution. For now, I will continue advancing with Microsoft Edge.
In any case, thank you very much.
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For this reason some advanced WebGL features/extensions may not work properly. 
