I installed the appstream package from the cosmic repository (0.12.2-2) in my bionic VM, and the crash went away. Looks like this might be https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=906538, reported upstream as https://github.com/ximion/appstream/issues/198 and fixed with https://github.com/ximion/appstream/commit/734e9da66bf12fcaa94c10465db2dcf8bb2b94cb.
I installed the appstream package from the cosmic repository (0.12.2-2) in my bionic VM, and the crash went away. Looks like this might be https:/ /bugs.debian. org/cgi- bin/bugreport. cgi?bug= 906538, reported upstream as https:/ /github. com/ximion/ appstream/ issues/ 198 and fixed with https:/ /github. com/ximion/ appstream/ commit/ 734e9da66bf12fc aa94c10465db2dc f8bb2b94cb.