Le problème :

libGL error: unable to load driver: i965_dri.so
libGL error: driver pointer missing
libGL error: failed to load driver: i965
libGL error: unable to load driver: i965_dri.so
libGL error: driver pointer missing
libGL error: failed to load driver: i965
libGL error: unable to load driver: swrast_dri.so
libGL error: failed to load driver: swrast

Le remède:

francois@portable-asus:~$ find .local/share/Steam/ | grep libgpg-error
francois@portable-asus:~$ rm .local/share/Steam/ubuntu12_32/steam-runtime/amd64/lib/x86_64-linux-gnu/libgpg-error.so.0
francois@portable-asus:~$ rm .local/share/Steam/ubuntu12_32/steam-runtime/amd64/lib/x86_64-linux-gnu/libgpg-error.so.0.8.0
francois@portable-asus:~$ rm .local/share/Steam/ubuntu12_32/steam-runtime/i386/lib/i386-linux-gnu/libgpg-error.so.0
francois@portable-asus:~$ rm .local/share/Steam/ubuntu12_32/steam-runtime/i386/lib/i386-linux-gnu/libgpg-error.so.0.8.0