A sliding glass door in the foyer of an office I worked in once just spontaneously turned itself into a pile of glass granules one day. I'm led to believe it's not a particularly infrequent occurrence.

I'll never get a glass top table after a friend's coffee table did the same. Yeah it was likely chipped or damaged or abused by years of coasters and glasses and controllers and books dropped on it, but one day we were minding our own business in the kitchen when we heard an unholy crash, come to find the tabletop in shards on the living room floor.

there's a YouTube video of someone making uranium glass that had this exact issue come up. Very interesting to see in practice

I think it was mostly during the cooling when the internal stresses are relaxing. NileRed - https://www.youtube.com/watch?v=RGw6fXprV9U