Diagram window
By default, the Diagram window is displayed in the upper right section of Modeler. You use the Diagram window to manage and maintain diagrams and the window automatically opens when you create or open a diagram.
If you open two or more diagrams, the diagrams become tabbed so that you can easily switch between them.
The Diagrams window does not dock so it behaves in the same way as a standard MDI window; using the window controls, you can minimize and maximize (and close) the Diagrams window according to the way you want to view a diagram. It is often helpful to maximize the area you have available for diagramming.
If you have many diagrams open, you can use the Arrange Windows dialog to organize those windows - on the Windows menu, click Windows.
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You can make more room available for diagrams by setting your panes to auto hide.
Note that when you select an item on a diagram, the Property pages display properties for the selected item.