Dude, where’s my theme? Using Modern Themes for Power Apps

Microsoft released a modern, refreshed look for Model-Driven Power Apps.

It will be enabled by default starting with the 2024 Wave 1 release.

End users will see the “Try the new look” toggle in the top header automatically enabled. Users will be able to turn it off individually unless an administrator has set the “New look always on” setting to Yes. 

Once this is turned off, the “Try the new look” toggle will disappear.

You’ll notice in the above screenshot that the theme changed with the removal of the “Try the new look” button.  The “Root16 Blue” was replaced by the default Microsoft dark blue.

Out of Configuration and into XML

The historic theming was configured in the classic designer by navigating to Advanced Settings -> Customizations -> Themes.  From there you could add a logo, and a handful of other colors using hex codes.

However, to leverage a theme with the new modern, refreshed UI, you’ll need to do more. You’ll have to create a web resource with your hex codes and use it in an “Override app header colors” setting as outlined in this link.

The new modern, refreshed UI theme offers fewer options than the old one. This could be seen as a positive as many of the old UI element colors were difficult to find. The Hover, Selected, and Pressed colors all refer to buttons in the various states.

After creating the web resource, copy the “Name” value, and add the “Override app header colors” to your solution.  Open this up, and add a new environment value which is the copied name from above (do not include the quotes “” that come for free when you edit the value the first time). Save and publish all customizations. Your theme should be back in order while using the new modern, refreshed UI. 

This process is a bit clunky, but it isn’t difficult.  I can see Microsoft changing this to be a configuration setting somewhere without the need to update XML and create a web resource.