I use mailto to send mail using RTL language like Hebrew. I send plain text as recommended inside that content, I place one URL link, which turn out to be a hyperlink in outlook, but the link got broken. What I found, there are some character like (Left-to-right_mark) got inserted inside that link though not visible.
I have checked the that when I send the text then there is no such character but it is appearing(though not visible) in the outlook. For this reason if you copy that link and paste it in address bar that also not work.