It looks like the icon has been lost.
The icons aren’t lost. Thumbnails have been generated. You can disable this in Preferences > Media.
Also, you can remove these thumbnails by right-click > Thumbnails > Remove.
I was referring to the icon (character) indicating the file is indexed.
Was:
Now:
Again, not lost, just changed. That is a little Finder icon denoting indexed files.
It looks a lot like the symbol for a broken unicode character.
I like the old one that matched the macOS icon for an alias. It’s more intuitive. A Finder icon isn’t meaningful, as all files are in Finder, whether indexed or in a database.
I just looked up another odd looking icon. Kind of a finder without a face, which means the file is a duplicate. The icons really aren’t intuitive to me.
I actually like these new icons