With long strings (or some other trigger, not sure yet), it seemingly duplicates + concatenates the result of step 1.
I'm not sure what the MINIMUM reproduction steps are, but so far this has been consistent:
of note, when I tested my reproduction steps, I noticed that it seems to add "#" before "Twisted_Codes", even though, for testing purposes, my string no longer has a "#". "Reveal" posted the following messages to chat (note that I also tried removing my nickname on the server since the nickname display begins with a hash mark)
[09:37:39] [Render thread/INFO]: [CHAT] "Room 0x7203cea5 Twisted_Codes would-be quencher>>>Room 0x7203cea5 #Twisted_Codes would-be quencher"
[09:38:11] [Render thread/INFO]: [CHAT] Your nickname has been removed!
[09:38:21] [Render thread/INFO]: [CHAT] "Room 0x7203cea5 Twisted_Codes would-be quencher>>>Room 0x7203cea5 #Twisted_Codes would-be quencher"
speaking of which, here's the full log file. I'm sure you'll find it forgive the Hex Casting pun enlightening: