The following shortcut keys and mouse clicks are available while editing a Schema:

Tab / Shift-Tab: Cycle back and forth through the edit tools on the toolbar
Right Mouse Click while Selection Tool is not Selected: Jumps to making the Selection Tool the active tool.
Right Mouse Click while Selection Tool is Selected: A quick menu appears to select new operators, schema properties, and perform edit functions.
Right Mouse Click while Wiring: Deletes the last wire segment.
'x' or 'X': Cycles the Selection Tool icon from an arrow to a small cross to a large cross (useful for lining up operators and pins).
Del: Deletes the currently selected item
Cntr-Z or Cntr-z: Undo
Cntr-Y or Cntr-y: Redo
Cntr-X or Cntr-x: Cut the currently selected item
Cntr-C or Cntr-c: Copy the currently selected item
Cntr-V or Cntr v: Paste the currently selected item
Shift-Left Mouse Double Click while over a generic hardware operator: Activates the connect to hardware dialog

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