Include your macOS version, the file format, and — if you can share it — the file that failed to preview.
First things to try
Check that the extension is enabled in System Settings → General → Login Items & Extensions.Restart Finder if thumbnails have not refreshed after installing.Confirm the file opens in another tool — corrupt exports will not preview.Cloud files must be downloaded locally before macOS can render them.
Refunds
Purchases made through the App Store are refunded by Apple, from your purchase history. If Apple declines and you think it should have gone through, write to us with the order reference.
Contact addresses and response times are placeholder — replace before launch.