See issue 33117, CCE on clone action in output window.
The core problem is that OutputTabTerm does not
TopComponent.Cloneable, but CloneViewAction is
Agreed that it is a poor default, but does not seem critical - any
component has the opportunity to override the list with a better set
of actions. Thus only really affects module developers, assuming all
kinds of TC's used in NetBeans have been checked for a sane action list.
Fixed as part of issue #33557.
*** This issue has been marked as a duplicate of 33557 ***
verified, closed - it's duplicate.