Strange question , does not affect operation .
Severity Count Data Context Binding Path Target Target Type Description File Line Project Error 8 SevenSegmentControl, Name='SevenSegmentUserControl' NumberColor Path.Fill, Name='top' Brush Cannot convert from type 'System.Windows.Media.SolidColorBrush' to 'System.Windows.Media.Brush'. Consider setting a converter on the binding.
if you change to Mode=OneWay, no error msg. (you dont need to use the 2ways)