Can't find "Allow topic owner and staff to mark a reply as the solution" Setting

I saw on your newly designed site that it is possible to “mark solutions as the official answer”. After doing some research I saw that there was a plugin for this, but now it seems to a native feature.

According to this Is there a plugin or option for users to mark "helpful" posts? and this Category setting to enable solutions doesn't stay checked post, this setting should be available when I click on some category, then edit and then settings. However, there is no setting “mark solutions as the official answer”. Is there some additional step needed to enable this?

(I’m using the newest version of Discourse)

It’s an official plugin (so, supported by the team, but not in the core).