When activating the Mint Theme I’m seeing a double-up of the showcased categories at the top:
It’s happening both in the Theme Creator preview as well as when I install it on my test site (Theme Creator)
Showcased Categories on its own seems fine when attached to another theme, so I’m thinking it’s a Mint issue?
Hmm, it looks like maybe the theme is rendering the Showcased Categories theme-component, but then the theme-component is also rendering itself by default in a different plugin outlet.
Yea I can repro - it’s even more fun if you set the showcased categories to use the below-site-header plugin-outlet. 
Fixed here, thanks for the report!
https://github.com/discourse/discourse-mint-theme/commit/0827b74b12e05a8374ff841460e86beb8052e2b1
