The Witcher wiki now has a light themed alternative for the wiki skin. To check it out, go to Special:Preferences, then choose the "Appearance" tab and click on the radio button next to "Hydra".
Alternative look for Yennefer
The outfit can be disabled in the Downloadable Content tab of the main menu.
Official developer's description:
- Check out this entirely new look for the mighty sorceress Yennefer of Vengerberg!