Listening to MenuBar changes (com.sun.star.awt.XMenuBar and com.sun.star.mozilla.XMenuProxy)

Hello everyone,

I am trying to figure out how which object implements the 
com.sun.star.mozilla.XMenuProxy interface.

I want to use that interface from a given XMenuBar to be able to listen 
to menu changes, obtaining the item id. However, as far as I can see, no 
class implements this interface.

If anybody knows of any alternative route to listen for menubar changes, 
any hep is appreciated. I am trying to use the accessibility
infrastructure but I haven't figured out how to get to the right object
to introspect.

Cheers,
Alberto Ruiz
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