Can I modify the theme used for my App UI extension?

Currently, there isn't a way to modify the visual look and feel of an App UI extension on its own. Instead, the App UI Extension should match the rest of your Oracle Fusion visual identity. That said, we are adding more capabilities over time for customers to enhance their own brand presence in their Fusion Redwood user interface and as those capabilities are added, your app UI extension will automatically inherit any customizations that are made.

Note that standalone Visual Builder contains the ability to overwrite the default Redwood theme.