Library Pane

Is there a way to PIN the library view on the Xcode desktop

If you option-click the Add button in the project window toolbar, the Library window will stay open. I don't know if that's what you mean by "pin the library view on the Xcode desktop", but if option-clicking isn't enough for you, you will have to explain what you mean by pinning the library view.
Library Pane
 
 
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