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Windows always has an opengl32.dll, but in virtual machines it often provides only OpenGL 1.1. Creating a context through glutin succeeds there and only the missing glCreateShader gives it away. That check ran in resume(), after the window adapter was created with the FemtoVG renderer, so the backend could no longer fall back. Probe for glCreateShader with a throwaway window in new_suspended() instead. The renderer creation then fails early enough for the fallback chain to reach the software renderer. Only a WGL context that lacks glCreateShader proves that the driver is a GL 1.1 stub. If the probe itself can't run, glutin may still reach a working driver through EGL, so leave the choice to it. Closes #12706 ChangeLog: Windows: fall back to another renderer when the OpenGL driver doesn't support OpenGL 2.0
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Windows always has an opengl32.dll, but in virtual machines it often provides only OpenGL 1.1. Creating a context through glutin succeeds there and only the missing glCreateShader gives it away. That check ran in resume(), after the window adapter was created with the FemtoVG renderer, so the backend could no longer fall back.
Probe for glCreateShader with a throwaway window in new_suspended() instead. The renderer creation then fails early enough for the fallback chain to reach the software renderer.
Only a WGL context that lacks glCreateShader proves that the driver is a GL 1.1 stub. If the probe itself can't run, glutin may still reach a working driver through EGL, so leave the choice to it.
Closes #12706
ChangeLog: Windows: fall back to another renderer when the OpenGL driver doesn't support OpenGL 2.0