[BUG] Ragnaros chest instantly despawns if theres only the Eternal Embers left inside it

[lavjamanxd]

1. Current Behavior

1.1. Description

We killed ragnaros today it dropped 4 embers. We are using group loot to hand out things (because of past incidents like alysrazor getting stuck in the air), we were at the end doing some calculations how many embers we need to finish the 25, so those items left inside the chest without anyone needing on it just waiting for the timer.
When all the items got handed out to the RL to do the item assignment, the chest instantly despawned and the items couldnt be looted anymore, the grouploot window was not reacting to need/greed/pass anymore.

1.2. How to Reproduce

       1. Group loot on
       2. Kill Ragnaros
       3. Need on all items (and get it handed out to someone) except the Eternal Embers
       4. The chest despawns with the quest items inside

1.3 Source Material

Sorry for the bad screenshot but thats what i have (you can see that the roll window is still active ticking, but the chest already gone...)

It is also visible on the /loot window that no one got it in the end.

2. Expected Behavior

Chests does not despawn while there are loot inside.

[Zereges]

Can confirm this happened to our raid as well. We contacted GM and the response was

After having looked into why this occurred I could not determine a reason for the Embers disappearing, it must therefore be a bug, please report it to our development team. Have a nice day.

[Amatyr]

Had similar to this but with Beth'ilac. Two on the quest, one pass, one Need. No loot roll triggered, no drop into bags, no Cinders on the body.