Steps to reproduce the bug.
1.Create new Quick UI application(File->New file or project >Qt QuickProject>Qt Quick Application!. Use default setting and set desktop as a target.
2.Open projects .pro file. Uncomment line DEFINES += QMLJSDEBUGGER
3.Push Projects button in left tab and check QML in projects run setting.
4.Choose project in target selector and set debug as build mode.
5.Push Start debugging button in left view.
6.Switch to debug mode with debug button in left tab.
7.Start QML observer mode with observer button.
8.Double click the last item in the observer, it is a white square.
9.A dialog named "select color" flashes then disappears.

Expected result:
The select color dialog can be used.
Actual result:
The select color dialog flashes for a seconds then disappears.