Win 7’s version activates via a button on the top right of Windows Explorer. It pops out and displays files like music, videos, HTML docs, photos, WordPad docs (but not Word’s .docx flies ...

By default, the preview pane takes up most of the work area when the Windows Explorer is maximized, leaving little room to display files and folders. You can adjust the border size.

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.

So, subject. Explorer's preview pane occasionally stops showing me previews. The problem files are almost always PDFs and it seems to occur more often on network mapped drives than local disks ...

It’s not huge, but it’s something. With the File Explorer PowerToy enabled, you’ll now be able to view .MD and .SVG files in File Explorer’s preview pane.