If File Explorer Preview for PDF is not working or displaying correctly and shows ‘INDEX OF…’ under Network folders, here's what you need to do.

Stop File Explorer From Displaying Frequently Used Folders Toggle Navigate, Preview, and Details Pane On or Off Open Files and Folders With a Single Click Select Items Using Checkboxes in File ...

But the latest update of the Windows 11 in the Insider Preview Build 22593 for Dev and Beta Channels users replaces the File Explorer home page with the newly minted "Home" feature.

Given how limited the preview pane already feels in Windows 10, even adding just two more file types feels like a huge improvement.

If you want to preview files in Windows 11/10 without opening them, then you can use QuickLook, File Viewer Plus, One Commander, or Seer app.