First off the amount of "pressure" caused by "hot air" trapped in a vehicle is absolutely not the answer. It's not even enough to be able to measure let alone place enough pressure on the glass to cause a blow out. Not physically possible here on earth - but let's not get into that.
Either way ........
All vehicle glass is tempered.
1) This process makes the glass more resistant to critical failures from impact, or pressure on the flat surfaces HOWEVER the edges when hit (impact) or put under pressure will fail.
2) Different materials like glass, your rubber seal on the door, or the steel of your car door all have unique thermodynamic properties (some are great conductor while others are not) and all of these materials expand and contract at different rates.
3) The most likely event is that something like a steel door jamb expanded (or contracted) in a spot at or near the edge of the glass and put enough pressure on it to cause a failure.
We have had this happen on a machine twice (a curved bubble front windshield) on a tele-handler (zoom boom).
One of these events was caught on our security camera.
Twice on the same machine on a sunny day.
After the second incident the manufacturer's service rep actually removed some material from two of the seating surfaces on the recessed surface (imagine a tray) the glass sat it as per manufacturer's recommendations and it stopped happening. These sudden blow out were occurring to other customers too and I guess that's what it was - the steel when expanding in the heat frame was putting enough pressure on the weak edge to cause a blow out.
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