"No Glyph" .notdef included in all Instances on Export

For some reason I can’t figure out, all of my exported instances have a new glyph added called “.notdef” and the glyph is an image that says “No Glyph”. Its the first glyph listed right next to my uppercase A.
Does anyone know what causes this? I can’t seem to find any empty, unused glyph spaces in my Master file.

Thanks again for the help.

The .notdef glyph is the glyph that is used to indicate to the user that a glyph is missing in a font.
It is part of the standard and therefore it is automatically added to your font on export.

Reference here: https://www.microsoft.com/typography/otspec/recom.htm (scroll down a bit)

I think I understand. So its not necessarily that my Glyphs working file is missing a glyph? Its just automatically included as a handy way to inform a user that a glyph they’re trying to use doesn’t exist in the font?

Exactly. :thumbsup: