I found a bug in the game. I am on WildGrowth EU.
After bug happened, some people in stormwind could not use mailbox, or fly, or use auction house, or invite to parties, and even got logout timer in stormwind.
Also a replica of my character sleeping was stuck forever in the inn:
How I did it:
I was in the BFD raid. I got out of my raid group before engaging Kelris. (raid was doomed and I was alone)
When timer to port to SW started, I waited until it was 5 seconds left.
Then I engaged Kelris. He immediately made me sleep and then immediately I teleported due to the timer.
Then I popped up in SW inn with a replica of me stuck sleeping, and people started reporting the above bugs.
I have images but forums disallow posting images here