When Item lending was updated there used to be a bug when a player is lending out a Mystic hat to another player. The hat would disappear when the other player logs out (supposing they have "Until Log-out" selected), leaving the other player bald. This has been fixed.[source needed]
The blue version used to be needed for a certain level 3 Treasure Trails emote clue, but was replaced with the Splitbark helm.