little holes in windows
the little hole is only in the inner of the two plastic window pressure panes at passenger positions.
the outter pane does not have a hole and takes the pressure difference of inside to outside pressure of 8 psi.
if this pane fails or blows out then the inner pane takes the pressure plus a small leak of cabin air out of the little hole.
between these plastic panes and passengers is a third pane of plastic which is there to stop the pressure panes being scratched and damaged by acid sweat and ball point pens.