UI has lost the default "Do you want to save Unnamed 1?" on quit, and just doesn't quit

So up until PCGen 6.07.02, If I have an unsaved character, and try to quit PCGen, I get a dialog mounted which asks if I wish to Save Yes/No/Cancel. "no" avoids saving, and then quits politely.

In overnight download-and-build from github, the dialog does not show - an attempt to Quit silently fails, doing nothing...
Only if I explicitly close the open character, and then ask to quit, will PCGen give in and let me escape.