In the screenshot you have provided, I feel like the Pin Planner Window is attached to the Quartus Window.
Could you "Detach Window" back to its own "Pin Planner" window so it is more convenient to look into.
Which thumb tack icon you have clicked? I assume it is the All Pins' thumb tack, then it is minimize at the edge of the window. You might need to look around.
See if you might happen to detach the All Pins from the Pin Planner. Then it might not in the Pin Planner GUI. It probably flying around somewhere. Close and reopen the Pin Planner GUI window might helps to resurface the window.
Best Regards,
Richard Tan
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