Having problems configuring each site themes settings when using the Domain Access module?
Firstly ensure that you have the Domain Theme module enabled - not just Domain Access!
Don't try change each sites theme settings via Appearance > Settings. That works fine when setting your Global Theme settings, but it doesn't work the same as setting each sites System > Site information, ie. by logging into each site and going to that page and saving.
To change each sites theme settings go to the Domain config page (/admin/structure/domain), and edit the site you want to change via the edit domain link. Within that area you will notice that there is a Themes tab. In there you will be able to configure each sites theme settings.
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