'{DependencyProperty.UnsetValue}' is not a valid value for property 'FocusVisualStyle'

Question

I have a weird error I\'m trying to debug with no luck.

I have subclassed hwndhost showing some content, I have the following function in that class to set to fullsc

Answer 1

Yet another way to cause mentioned exception is when you declare StaticResource after using it, for example in style declaration.

WRONG

CORRECT