Step 1: Launch a new Finder window by choosing New Finder Window under the Finder’s File menu.
Step 2: Navigate to a desired file or folder and click the item in the Finder window while holding the Control (⌃) key, which will bring up a contextual menu populated with various file-related operations.
Step 3: Now hold down the Option (⌥) key to reveal a hidden option in the contextual menu, labeled “Copy (file/folder name) as Pathname”.
Step 4: Selecting this option will copy the complete, not relative, pathname of your item into the system clipboard.
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