My photoshop files (PSD) do not show an image preview / thumbnail in Windows File Explorer, as do JPG and other image files. I see an option when saving to save a thumbnail, but this does not show up in Windows File Explorer. (Windows 10, Surface Studio)
How do I get PSD image thumbnails / previews for Windows Explorer?
Basically since Windows does not support PSD thumbnails, a third party codec is needed:
Alternatively, you can go the whole way and try MysticThumbs.
Not just PSD, not just RAW, and not just more, but 70 - yes that's right, 70 (currently) file formats, plus a QuickView pressing the space bar like Mac does, plus customisations to appearances which include transparency checker-boarding, sizing and a whole lot more. It costs a little more but is a very powerful tool for artists. It has a 14 day trial period.