FAQ: how to prevent {x:Null} from being written by XAML writer
Internal thread that may be of use to more people:
Question From: Microsoft Developer
Is there a way to configure XAML writer (XamlWriter.Save() or XamlServices.Save()) to not to serialize null properties. Right now I get "{x:Null}" written for them?
Answer From: XAML Team Developer
You need to attribute the affected properties with [DefaultValue(null)]
Mike Hillberg's "Being Written by XamlWriter" is a good read for this kind of info
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