Same for me
But 5min after rolling out the bugfix I noticed, that you cannot take for grnted that a window is open on every system ...
And I noticed that even with a few windows open - there is an issue
... if the current Jmp window is no "window" - which seems to be the case for the Home Window and the Window List.
Just install the attached AddIn and try to run AddIn/Current Window() - first from a script, report or table window and then from the Home window.