Site Health: mark installed default themes

[tobifjellner]

In the list of installed themes, it would be good to somehow indicate which of the installed themes that are default themes (and therefore could be good to leave installed).

[Clorith]

I'm not sure if that's needed, it already declares "by the WordPress team" with them, so you know they're the official themes, adding any kind of indicators feels a bit much for debug data?

[Presskopp]

I'm with Clorith here and don't see the use case. There's no movement in 6 years, therefore I'm closing the ticket.