We added combobox in a screen which is internal frame.it works fine. The same combobox is added in another screen in the combobox is added in a panel inside a JTabbedPane and whole thing is placed in a internal frame. In this case the combobox does not toggles the popup when we click it continuously. Also I added normal in that screen, it does not toggles the popup. Even if we add the combobox inside table also, the popup is not toggled while using mouse.