Command entry: 
Slate Material Editor
Menu bar
Edit menu
The Edit menu has commands for editing the currently active View, and for updating material Preview windows.
Some menu choices are also accessible from toolbar or navigation buttons, so this topic shows the button alternative along
with the menu choice.
Interface
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Delete Selected
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In the active View, deletes the selected nodes or wires.
Keyboard shortcut: Del
- Clear View
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Deletes all nodes and wires in the active View. 3ds Max displays a warning that asks if you really want to do this.
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- Update Selected Previews
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When Auto Update is off, choose this to update the Preview windows for selected nodes.
Keyboard shortcut: U
- Auto Update Selected Previews
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Toggles automatic update of the selected Preview windows.
Keyboard shortcut: Alt+U
