Diigo highlighting not active inside a module's text ?

[yssman]

I installed Diigo on my webbrowser and also activated it in my Canvas profile. 

While I can use the extension without problems on other sites, as soon as I move into the Module's text to make highlights, it doesn't work any more. It's almost as if the module is shielded from using the Diigo extension on it. 

Does anyone know about this problem? Any solutions?

Thanks.