This transformation option can be used to apply the transformation state of one viewport to other viewports. Useful if you want multiple viewports to have the model oriented the same, and you did not link the viewports for transformations before applying any transformations.
The use of this option consists of:
Selecting the viewport (one only) containing the transformation state desired. (You can do this with the Viewport Quick Action icon, or under Editor Function → Global Transform in the Transformation Editor Dialog.)
Selecting Copy Transformation State under Editor Function in the Transformation Editor dialog.
Selecting the one or more viewports to receive this transformation state. (As in 1. above)
Selecting Paste Transformation State under Editor Function in the Transformation Editor dialog.