Run attached code snippet on Windows and Mac. It tries to imitate drag event using glass robot by calling

                robot.mouseMove(x + 10, y + 10);
                robot.mousePress(1);
                robot.mouseMove(x + 10 + N, y + 10 + N); // in loop

on Windows this works perfectly showing next events:

# MouseEvent [source = Rectangle@13f7175, target = Rectangle@13f7175, eventType = MOUSE_MOVED, consumed = false, x = 10.0, y = 10.0, button = NONE]
# MouseEvent [source = Rectangle@13f7175, target = Rectangle@13f7175, eventType = MOUSE_PRESSED, consumed = false, x = 10.0, y = 10.0, button = PRIMARY, primaryButtonDown]
# MouseEvent [source = Rectangle@13f7175, target = Rectangle@13f7175, eventType = MOUSE_DRAGGED, consumed = false, x = 20.0, y = 20.0, button = PRIMARY, primaryButtonDown]
# MouseEvent [source = Rectangle@13f7175, target = Rectangle@13f7175, eventType = DRAG_DETECTED, consumed = false, x = 20.0, y = 20.0, button = PRIMARY, primaryButtonDown]
# MouseEvent [source = Rectangle@13f7175, target = Rectangle@13f7175, eventType = MOUSE_DRAGGED, consumed = false, x = 25.0, y = 25.0, button = PRIMARY, primaryButtonDown]

on Mac mouse_moved events being produced instead of mouse_dragged:

# MouseEvent [source = Rectangle@299320cf, target = Rectangle@299320cf, eventType = MOUSE_ENTERED, consumed = false, x = 10.0, y = 10.0, button = NONE, primaryButtonDown]
# MouseEvent [source = Rectangle@299320cf, target = Rectangle@299320cf, eventType = MOUSE_MOVED, consumed = false, x = 10.0, y = 10.0, button = NONE, primaryButtonDown]
# MouseEvent [source = Rectangle@299320cf, target = Rectangle@299320cf, eventType = MOUSE_PRESSED, consumed = false, x = 10.0, y = 10.0, button = PRIMARY, primaryButtonDown]
# MouseEvent [source = Rectangle@299320cf, target = Rectangle@299320cf, eventType = MOUSE_MOVED, consumed = false, x = 30.0, y = 30.0, button = NONE, primaryButtonDown]
# MouseEvent [source = Rectangle@299320cf, target = Rectangle@299320cf, eventType = MOUSE_MOVED, consumed = false, x = 35.0, y = 35.0, button = NONE, primaryButtonDown]
# MouseEvent [source = Rectangle@299320cf, target = Rectangle@299320cf, eventType = MOUSE_MOVED, consumed = false, x = 40.0, y = 40.0, button = NONE, primaryButtonDown]

although dragging "by hands" without robot works correctly.