How do I get QuickLook in macOS to display `.mojo` files?

* macOS 13.6 Ventura * Mac Mini M1 Can someone remind me how to get QuickLook to display .mojo files, or any unknown file to display its contents. Some of my code source files display with code highlighting and everything, but .mojo files do not even display in plain text. There's nothing special about .mojo files; they're just plain text files. Indeed, I've already got them configured to open in Cursor editor when double-clicked. It's just [space] that doesn't work.