RSRP-469093: Static Resource from another project not found in Designer

I have three projects: the main application, the controls and the styles. A resource dictionary from styles is included in the app.xaml of the main project. The controls work fine in Designer, but Resharper warns about not finding the static resources. I tried to include a fake app.xaml in the controls project (https://stackoverflow.com/questions/27899875/wpf-resource-is-not-found-by-resharper-in-design-time-but-solution-builds), but that only works for resources explicitly included in this app.xaml file. As you can see in UserControl1, ColorA is correctly included directly from the controls app.xaml, ColorB is ignored (probably because it is included as DynamicResource) and ColorC and ColorD are marked as not resolved.
Is there a way to tell Resharper where the correct resources are? I don't want to include them as project resources in the controls project, because they are not needed in all use cases.