Hey @chris m12​ Racheal from the Support Engineer team here 👋

While there is not an out of the box way to do this, you could use a possible workaround. You'd want to create a custom data attribute that you store in the Contact object. You can name it whatever you want, and would want to give it a Boolean value (EX "dark_mode": true). Then, based on the value of that attribute you can choose to send your customer the dark-mode version of the Outbound Chat or the regular version. You would set that in the audience rules for the two Chats.

This is a great one to flag on the @Product Wishlist​ !