Created attachment 122991 [details]
FontForge screenshot of u (U+0075)
On the u symbol (U+0075), there is a point behind the Anchor-18 as seen in FontForge (see attached screenshot)
Obviously, this is not visible on normal rendering.
But, I'm making some experiment with Opentype.js (http://opentype.js.org/) and when parsing the font, it create a second contour for this useless point.
Concerned file name in my system: DejaVuSans.ttf
System is Archlinux and up to date.