#1 Right-click passes on to the next handler

[Guy H]

When I right-click the container to show the context
menu, then select an item from the menu, that option is
handled but then a 'What's This' menu option opens. I
think this means the right-click is not marked as
handled by the container so after it returns control
the right-click is sent forward to the next item.
You can see this behaviour when you select 'next tab'
(you get a 'What's This' option for the container), and
also when you select 'Container Options...' (you get
the help context for the dialog).