server@phoenix ~ $ apt list --installed | grep -i mesa

WARNING: apt does not have a stable CLI interface. Use with caution in scripts.

libgl1-mesa-dri/bionic-updates,now 18.2.8-0ubuntu0~18.04.2 amd64 [installed,automatic]
libgl1-mesa-glx/bionic-updates,now 18.2.8-0ubuntu0~18.04.2 amd64 [installed,automatic]
libglapi-mesa/bionic-updates,now 18.2.8-0ubuntu0~18.04.2 amd64 [installed,automatic]
libglx-mesa0/bionic-updates,now 18.2.8-0ubuntu0~18.04.2 amd64 [installed,automatic]
mesa-utils/bionic,now 8.4.0-1 amd64 [installed]
mesa-va-drivers/bionic-updates,now 18.2.8-0ubuntu0~18.04.2 amd64 [installed,automatic]
mesa-vdpau-drivers/bionic-updates,now 18.2.8-0ubuntu0~18.04.2 amd64 [installed]