In case you missed it, a video from one Twitter user shows an Xbox Series X spewing what appears to be an alarming amount of white smoke from the top-mounted exhaust fan.
Before we call the fire department, however, it's worth noting that the videos, while fun to watch, are not exactly concrete evidence. First of all, there are just two videos, so if it were a hardware issue we would expect to see more. Secondly, the videos are pretty sparse. They show "smoke" but no subsequent fire or further insights into what happened later.
While it's not totally clear what's happening in these videos, a separate account on Twitter is suggesting that the consoles have actually been flooded with vape mist. The demonstration looks pretty credible.
Other issues, such as whirring and malfunctioning disc drives inside the Series X may be the real fire that Microsoft needs to put out.