You're correct that back-end pages are still just pages. The distinction between front-end pages and back-end pages is made through taxonomy. In fact, if you poke around in the Configuration Editor, you will see the Guid ID that is associated with the root of the front-end & back-end taxonomies.
All this being said, I can't steer you any further than this. I tried the following code:
var pages = App.WorkWith()
.Where(p => p.RootNode.Name ==
This feels like it is close, but I'm getting a "Object reference not set to an instance of an object." error. I'll keep playing though. If you discover a solution, I'm anxious to hear it. Otherwise we'll find out the details from the team.
P.S. For anyone else also trying to interact with the Fluent API, the default Web Application project is missing an assembly reference for the Facades. Add a new reference, go into the "bin" folder and then add references for those assemblies. Visual Studio should now be able to resolve those Facade references.
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