I assume from your title, this has happened before?
Seems like there must be some unusual stress on the window.
I assume it is plexiglass?
I wonder if making it out of Lexan would work better.
I tested a piece of Lexan vs Plexiglass and the Lexan was very ”breakproof” compared to plexiglass. I think it has other issues (scratches easily and gets cloudy with UV exposure maybe), but tough stuff.
Greg