Process/Task scope is not obvious

When no task is selected in a process definition diagram, the Variable tab shows a list of global variables for this process. 

When the user clicks on a task (and thus selects it), the Variable tab does not show any variables (unless there are local variables to this task). Although totally correct in terms of logic and scope, this is not obvious.

The selected task could be highlighted better, and the textual feedback in the list could change to "No local variables found" or smth similar.

(Feedback from Training participant)