What Themes 2.0 Changes
Themes 2.0 changes how Yeja looks to you: the colors, text, surfaces and type of the app around your work. It doesn’t change your Atelier. To change how your Atelier looks to visitors, use Themes & Style in the Atelier editor; see Atelier.
Yeja Themes, the older theme editor, is now part of Themes 2.0, and old links to it open Themes 2.0. Light, Dark and High Contrast are a separate setting; see Account And Sign In.