https://learn.microsoft.com/en-us/dotnet/api/system.windows.media.textformatting.textrunproperties?view=netframework-4.8.1
TextRunProperties Class (System.Windows.Media.TextFormatting) | Microsoft Learn
Provides a set of properties, such as typeface or foreground brush, that can be applied to a TextRun object. This is an abstract class.
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