With ES 3.0 and up the GL_MAX_SAMPLES query is available and is guaranteed to be at least 4. With ES 2.0 there is no such query. While what we report from supportedSampleCounts() has little significance with OpenGL (for the window's color buffer it is anyway the QSurfaceFormat that decides, not QRhi), QRhi users such as Qt Quick may rely on supportedSampleCounts() returning real values and may, for example, warn if the value attempted to use is not in the supported list. (even if MSAA is fully functional) Avoid getting such warnings on a pure ES 2.0 implementation with 4x at least. Pick-to: 6.7 6.6 6.5 Fixes: QTBUG-120474 Change-Id: I8a34a8bc9ce37ce951fdf7794247e8db44435d41 Reviewed-by: Andy Nichols <andy.nichols@qt.io>