User can accidentally make 3D View to freeze. Steps to reproduce:

• Create/open a project
• Import attached 3D assets to the project
• Double click Box component in Components view to edit it
• Right-click in 3D view and choose "Create -> imported models -> QtLogo
• Save changes
• Go back to Screen01.ui.qml file
• Double click QtLogo  in Components view to edit it
• Right-click in 3D view and choose "Create -> imported models -> Box (that now contains also QtLogo model)
• Save changes
• Reset 3D view
• -> 3D view freezes, Code view shows error "Qt Quick emulation layer crashed"
• Seems to reproduce only if you are trying to add a model that includes the model you are currently editing.