Uninstalling macOS App Extensions from System Preferences I'm a developer, but it is more of a user-centric question.

How can one "unregister" a Finder Sync (or any other, presumably) OS X / macOS App Extension so that it disappears from System Preferences > Extensions?

I've removed the app that's hosting it (FinderSyncTest), but it still shows here:
I found my extensions in:

/System/Library/PrivateFrameworks/ShareKit.framework/Versions/A/PlugIns


Delete FinderSyncTest.appex, restart Finder, and it should be gone.