[ This is cross-posted across several mailing lists for maximum visibility. Please respect reply-to and keep replies to x11 at FreeBSD.org . Thank you! ] In order to improve support for the new lkpi based graphics drivers (drm-kmod) and to improve the graphics stack we have switched mesa to prefer DRI3 over DRI2. This was done in r528071. For those using drm-kmod, this should improve performance somewhat, and more importantly alleviate the use of the FIXDRM option (now removed) in xorg-server. However, for those of you using graphics/drm-legacy-kmod or the drm drivers in base, this change can cause issues. If you are experiencing problems when running OpenGL applications, you can force the use of the DRI2 backend. To force mesa to use DRI2, set the environment variable LIBGL_DRI3_DISABLE to 1 before starting any OpenGL application. The easiest way to accomplish this is by adding it to either your shell startup file or ~/.xinitrc. As an example, for users of [t]csh, put setenv LIBGL_DRI3_DISABLE 1 in ~/.cshrc. For users of bourne type shells (sh, bash, ksh, zsh, ...) instead put export LIBGL_DRI3_DISABLE=1 in ~/.profile If you are using these legacy drivers, I'm also very interested in hearing what issues you are facing that prevents you from using the new lkpi based drivers. Regards -- Niclas Zeising FreeBSD Graphics Team