This workaround solved it for me, my result from $ apt-cache policy xfce4-session exo-utils:
xfce4-session: Installed: 4.12.1-3ubuntu3 Candidate: 4.12.1-3ubuntu3 Version table: *** 4.12.1-3ubuntu3 500 500 http://no.archive.ubuntu.com/ubuntu bionic/universe i386 Packages 100 /var/lib/dpkg/status exo-utils: Installed: 0.12.2-0ubuntu0.18.04.1 Candidate: 0.12.2-0ubuntu0.18.04.1 Version table: *** 0.12.2-0ubuntu0.18.04.1 500 500 http://no.archive.ubuntu.com/ubuntu bionic-updates/universe i386 Packages 100 /var/lib/dpkg/status 0.12.0-1 500 500 http://no.archive.ubuntu.com/ubuntu bionic/universe i386 Packages -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1808694 Title: exo-compose-mail-1 includes 64-bit installation prefix on 32-bit To manage notifications about this bug go to: https://bugs.launchpad.net/exo/+bug/1808694/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs