[Xcb] status of XCB + Xlib + GLX -> OpengGL

[Cosmin Apreutesei]

Hi Rémi, thanks for answering.

> This is unfortunately correct.

Shouldn't there be a big red flashing warning about that on the XCB
homepage and on the opengl tutorial? I feel quite mislead.

> - use XCB only for requests/responses, not events,

Ok (sigh).

I'm also tempted to try the Qt kludge[1] of calling the
XESetWireToEvent hook (I assume that's the only way OpenGL can hook
into Xlib anyway, right?)

[1] https://github.com/qtproject/qtbase/blob/1d8b6597a36f266c3384553365326cf7ec9f8641/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qxcbglxintegration.cpp#L128