Hello,
Have you tried to reinstall onboard and python-virtkey with the Synaptic Package Manager?
Have you tried to use a layout stored in your home directory instead of letting onboard create the layout when it gets started?
Are you using it on the local computer or are you forwarding your gnome session to a remote computer and working remotely? (On my system, onboard is working locally, but not remotely.)
Cheers
Francesco
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