Related to RT-13889.

While attempting to workaround the problem discussed in RT-13889, I discovered that if I try to programmatically hide the menu (by calling MenuButton.hide(), or MenuItem.getParentPopup().hide()) that the popup was successfully hidden but it somehow locked the UI from receiving further events until I minimized and restored the application or in some other way unfocused and refocused the FX application. Sample code is attached.

Steps to Repeat:

- Run the attached program
- Click the "Toggle" button to see that show/hide work just fine when being called from another control's event handler
- Now drop the Menu Button and click the black Rectangle. The EventHandler on the rectangle calls hide on the MenuButton (I'm trying to do this because of RT-13889). The menu is successfully hidden, but notice how suddenly you can't interact with the buttons anymore until you focus away from the FX application and then refocus it.