Gray cell in font view?

in font view, what’s a gray cell containing a glyph signify?

Glyph has been changed since the last save.

In practice, it seems like the grey indicates that the glyph has been changed since the last file open. The grey doesn’t go away after a save. If the grey should clear upon saving the Glyphs file, then consider that a bug.

thanks, I figured it was something like that, but yes: grey doesn’t go away after a save, hence my confusion.

This is due to changes in the document architecture in Lion (in the non App Store version you can still revert to the old behavior in the preferences). I did not manage to find a good solution. So yes, this is a bug.