I noticed this block of code in Window.java:

    void preProcessKeyEvent(KeyEvent e) {
        // Dump the list of child windows to System.out.
        if (e.isActionKey() && e.getKeyCode() == KeyEvent.VK_F1 &&
            e.isControlDown() && e.isShiftDown() &&
            e.getID() == KeyEvent.KEY_PRESSED) {
            list(System.out, 0);
        }
    }

Not that ctrl-shift-F1 is that common of a keystroke, but this does create
an undocumented edge case. After talking to Tom Ball, the original author of
this code, we have decided to keep the debugging hook. However, we need to
document it properly.