Hello, >VBOX_USE_SYSTEM_XORG_HEADERS, VBOX_USE_SYSTEM_GL_HEADERS >VBOX_NO_LEGACY_XORG_X11 last 2 options only available on 5.2 ! . I was already adding the XORG_X11 one, because cherry-picking that upstream fix already in 5.1 branch :) added the GL one, thanks! G.