When i click on the Debugger pane in Juno menu nothing happens

When i click on the Debugger pane in Juno menu nothing happens, no pane opens.

In the screenshot that you are showing, the Julia session is not even started.

The debugger pane should open automatically when you are debugging something. Have you tried the example given in the documentation?

http://docs.junolab.org/latest/man/debugging/