I am told that the problem is more serious.
For many a month I would close my PC, put it in the bag provided, and it theoretically would go into controlled shut-down. Some of us noticed that it didn't always. This is a software glitch.
Remaining under power, and generating heat, it seems that the bags may catch fire before the PC, but once they have, you have a battery runaway. Unlikely to be an issue on a short-range flight, but not so clear for a long-range.