Customizing the File Explorer Navigation Pane
Use Folders to Customize Quick Access in Navigation Pane
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WinCustomize Forums
WinCustomize Forums
Make use of Empty folders to customize Quick Access in the File Explorer navigation pane.
This works a little like my Taskbar Separators. Create NEW folders and name them as Section headers, and then give them a unique icon. You can use a different icon for each separator, or use the same icon for each.
As an example, here's a pic of my Quick Access using a green star icon. Have FUN! 
