ContentProperty should name an existing property
ProprietaryFlags a [ContentProperty("X")] whose target property the attributed type does not declare, which XAML only discovers when the content is parsed.
OpenRewrite. Recipes. CSharp. CodeQuality. Wpf. FindMissingContentPropertyTargetmod run . --recipe= OpenRewrite. Recipes. CSharp. CodeQuality. Wpf. FindMissingContentPropertyTargetInstall it once, then run it on every repository under the current directory. New to the Moderne CLI? Set it up.