Comedy?

Also, that shirt shouldn't have happened.

Bozo's got a flask bubbling away on a hot plate, is inserting a flame into a GLASS carboy, and has ZERO eye protection on. Bozo got lucky this time.

My guess: the probe/rod he was using was inside the neck of the carboy, preventing the gas from escaping through the neck fast enough to keep the internal pressure lower than the breaking-point of the glass. Had he not been obstructing the opening all would have gone to plan.

...but yeah, safety goggles would have been a good idea. That whole thing could have turned out much, much worse.