Question
Charachter suddenly replaced in html/chm output
I'm practicing with CourierNew box drawings characters.
Before, looking just fine:

Then I replaced the XYZ with new "light horizontal" characters. (copy and paste from same line.) The html5 (or chm) output suddenly has replaced the "down and horizontal" character with something unknown - even though I didn't touch any of the characters in that area.

I can't understand why this happens, and how to avoid it.
