[chirp_users] What did I do wrong? Bricked TH-9800

So I let the smoke out of my TYT TH-9800 when connecting it to program using CHIRP. I had previously programmed it with CHIRP with no problems. However, this time I wasn't paying attention and left the radio on when I plugged in the USB cable. It instantly shut down and there was a wisp of smoke from the back of the radio.

What did I do wrong? Plug it in while powered on?