fontforge/fontforge — pull request #1101 by JoesCat (2014-01-09 05:26:16+00:00)
Title: Small Greek Letter MU and the Scientific Micro Sign look alike

See thread - subject "[Fontforge-users] Character Glyph questions",
2014jan7 where it was noted that the two characters look alike.
http://sourceforge.net/mailarchive/message.php?msg_id=31817487