It'd be nice to make "orage" calendar application give some hint about icon-middle-click behavior. Middle-click opens the "Global Time" section, but that behavior is not documented anywhere. I discovered this accidentally after using orage for like 3 years. The proposal is to add some hint about that. For example, in orage > menu > view > show global time (icon middle click).
The orage project is not maintained anymore and has been archived. Closing bugs.