I am afraid I am not a WPF expert myself, we've just recently started working on a project where we decided to use WPF for the first time. I wanted to use NLog to log some info to the UI as we are used to, but then I saw there are no targets for WPF controls.
There is already some history with WPF RichTextBox https://nlog.codeplex.com/workitem/6272, there is even some NuGet package https://www.nuget.org/packages/NLog.Wpf.RichTextBox/, but not sure if these solutions still work.
That one is for WinForms, WPF has its own RichTextBox and other common text controls.
I think it would be very useful to have those as WPF is the way to go for C# desktop apps for a long time now instead of WinForms. I am really surprised NLog doesn't support any WPF targets already, quick Google search shows people need it.
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