Comment 2 for bug 1876882

Hello Mr. Aaltonen, Mr. Zemczak,

Per the distro packaging guidelines for Intel/Iris [1], please add libepoxy 1.5.4-1 to the set of packages to backport to bionic in this set and build the xorg packages against it instead of the older libepoxy. This is to avoid a mixed i965+iris driver situation that is not recommended.

Alternatively, mesa's debian/rules can be adjusted by adding `confflags_GALLIUM += -Dprefer-iris=false` immediately after `GALLIUM_DRIVERS += iris,` to avoid the dependency bump and retain i965 as the default OpenGL driver for all Intel hardware like previous mesa builds for 18.04.

[1] https://lists.freedesktop.org/archives/mesa-dev/2020-January/224027.html