1. Create new QML project.
2. Select main.qml file.
3. Switch to Design mode.
4. Drag List View (or Grid View) to Form.
5. Right click on a View -> Edit List Model ...
6. Double click to the right of the right header.
    
7. Creator crashes.

I suppose in QmlDesigner::ListModelEditorDialog::changeHeader() the value of the column acts as an array index without checking for validity, although the connected signal QHeaderView::sectionDoubleClicked in this case gives -1.