Application menus missing

[Chris Jefferies]

Since upgrading to Ubuntu 16.04 LTS, most applications no longer display menus. The Chrome browser is an exception, the menus appear as normal - File Edit View etc. Application menus appeared normally before the upgrade (from 15.10).

I'm running Ubuntu on a System76 laptop but suspect this is not relevant as I've noticed other users are having the same issue on other hardware.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: ubuntu-release-upgrader-core 1:16.04.12
ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6
Uname: Linux 4.4.0-21-generic x86_64
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: Unity
Date: Tue Apr 26 11:36:29 2016
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=en_GB:en
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: ubuntu-release-upgrader
Symptom: release-upgrade
UpgradeStatus: Upgraded to xenial on 2016-04-23 (2 days ago)
VarLogDistupgradeTermlog: