Feature summary (what you would like to be able to do and where):

Color scheme (maybe also typography) settings applying to all wikis

Use case(s)

As a cross-wiki user, I'm operating across a lot of different wikis. I want to have the same reading experience on all of them. To do that, I currently need to go to each wiki individually to change the settings there. I want to be able to use one menu applying to all wikis.