Another workaround: Downgrade indicator-appmenu to version 0.3.1-0ubuntu2 (oneiric version).
Conclusion: There's a regression from version 0.3.1-0ubuntu2 to 2.31.20-0ubuntu1
Another workaround:
Downgrade indicator-appmenu to version 0.3.1-0ubuntu2 (oneiric version).
Conclusion:
There's a regression from version 0.3.1-0ubuntu2 to 2.31.20-0ubuntu1