Use the PART_ prefix for template part names
ProprietaryFlags a [TemplatePart(Name = ...)] whose name does not start with PART_, the WPF convention for elements a control looks up in its template.
OpenRewrite. Recipes. CSharp. CodeQuality. Wpf. RequirePartPrefixInTemplatePartNamemod run . --recipe= OpenRewrite. Recipes. CSharp. CodeQuality. Wpf. RequirePartPrefixInTemplatePartNameInstall it once, then run it on every repository under the current directory. New to the Moderne CLI? Set it up.