Pin it when you want to browse, search or drag instead of pasting straight away.
The popup closes as soon as you paste, which is what you want most of the time. When you want to look around instead, pin it.
Pinning is what makes browsing, dragging and renaming comfortable: the window does not vanish the moment you let go of a key.
The pin has no shortcut until you give it one, in Preferences → Clipboard and popup. It only pins an open popup; it never opens one.
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