I was able to create a hidden, modal dialog underneath a different window in the designer. Since the modal dialog can’t lose focus, the window with the higher z-index can’t be moved out of the way. If you don’t know the dialog is there, the application appears locked up.
- Open a window and make a trivial change, e.g. move a component
- Select a component and open the Component Scripting dialog. My component has a script defined, but I’m not sure if that makes a difference.
- Select File > Open.
This causes the Save Changes? dialog to open (Would you like to save your changes … Yes/No/Cancel), but it appears underneath the Component Scripting window.
The modal dialog still has the keyboard focus, so you can dismiss it with: Tab, Tab, Space. Until I figured out what was happening, I was having to force quit the Designer in the Task Manager. This is Ignition 7.6.3.