The lines have uneven thickness

[XMJLXMJL]

Maybe due to the boundary constraints of the "RichItemContainer", some of the edges of the lines get clipped, which makes it look a bit weird. Is there an easy fix for this?

[mircea21S]

This could be caused by the Container that holds the ContentPresenter, I am not 100% sure. You can try to put a canvas behind your line when styling it, then do the logic to draw using TopChanged and LeftChanged events to draw it on that mini canvas. Have a look at this for more information: http://drwpf.com/blog/2007/12/28/cliptoboundsmaybe/
I will try to investigate it also and come back with any relevant solution or information if it's the case.

[XMJLXMJL]

Cool! Amazing! It's fine now!

Should I close this issue?

[mircea21S]

Don't close this yet, I want to investigate a bit more, but I think I won't be able to do anything as this is the design I will keep: the user is responsible for whatever displays inside RichItemContianer.