The bug

Named items' names are slightly orangish in glow item frames in complete darkness. I expected them to be white not orange. The reason for this is that normally the colour is white in full light, and since glow item frames make items appear as being in light level 15, the colour should match it in full light. Comparatively, the colour of a custom name in a regular item frame renders dark, so it doesn't match this either.

Steps to reproduce

1. Name item in an anvil anything you want
2. Go in a completely dark place (can't be night time on the surface because it isn't completely dark )
3. Place a glow item frame
4. Place the named item in it
5. Look at the glow item frame

 Notice the colour of the text is slightly orange, not white

Additional information

The colour appears to be 127, 103, 77, at least in the attached photograph. This is a brownish colour on its own, but if it were in daylight it would presumably appear as being orange.