Guild Charter Can Only Be Registered From Backpack

[JoLiKMC]

Note: This issue is a repost of Turtle WoW Issue #517: "Guild Charter won't register".

Issue

A player can only register their guild if the Guild Charter is in the main, 16-slot Backpack.

Reproducing the issue

How to

1. Go into any capital city and purchase a Guild Charter from a Guild Master. Put the Guild Charter in a secondary bag.
2. Have the Guild Charter signed by 10 people.
3. Return to a Guild Master and try to register your guild.

Expected behavior

The player's guild should be registered and become active.

Actual behavior

Nothing happens when clicking the turn-in text.

Further details

I thought this was specific to Turtle WoW but, apparently, this is entirely a MaNGOS issue. This has been the case since at least when Nostalrius Begins was around. So, here I am.

[ljwlaji]

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