A number of consequences of the new rhi-based backingstore composition were not handled. Most importantly, the fact that RasterGLSurface is not a thing anymore in practice causes challenges because we can no longer decide just based on the surfaceType what a QWindow with OpenGLSurface would be. (a plain GL window or a GL window with a backing store?) Also, the backingstore needs to be able to initialize its backing QRhi by itself, because with eglfs going through OpenGL is the only way. Amends 68a4c5da9a080101cccd8a3b2edb1c908da0ca8e Fixes: QTBUG-102750 Change-Id: Ia1ca59d01e3012264a76b50e591612fdcc2a0bd6 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Andy Nichols <andy.nichols@qt.io>