how to change appearance of document icons

Let’s see if this issue happens in Safe Mode:

1. Shut down your Mac.
2. Press and hold the power button on your Mac. As you continue to hold the power button, your Mac turns on and loads startup options. When you see Options, release the power button.
3. Select your startup disk. It's named Macintosh HD, unless you changed its name.
4. Press and hold the Shift key, then click the “Continue in Safe Mode” button below your startup disk.
5. Log in to your Mac. You might be asked to log in again.

If the issue doesn't continue in safe mode:

Leave safe mode by restarting your Mac normally, then try to reproduce the issue.

If the issue doesn't return, it might have been resolved by the other things that safe mode did at startup, such as checking your disk and clearing caches.

Let me know how it goes! 🙏

Good luck! 👋🏼😉

please see Change icons for files or folders on Mac - Apple Support

Okay, rename the file.

The name does not matter.

The renaming subroutine triggers the icon refresh.

Here’s an undocumented little tip:

Click to rename the file, but instead of renaming it, just push the return key and watch the icon magically change. 😉

Have a great day! 👋🏼😁

These are the proper macOS icon views which are not the same as each has the document type stamp that appears on the icon. The exception is the PDF which when multi-page, will have that black binder on its left edge, and if single-page, will have the PDF lettering to indicate it is a PDF.