Connecting a glass breaker to a non-locking joint sounds potentially very painful.
Something like a Resq-me or Lionsteel Eskaper aren't that big if you need a glass breaker?
Have you watched the video? I don't want to place the glass breaker on the tip of the can opener. But on the back side of it when it is closed, just like the guy in the video does with modified rescue tool glass breaker. This means you would have to remove it to use the can opener but that is exactly why I want it there as I don't use the can opener much.
And I know about resq-me and intend to buy one for my car (just checked the other day if my side windows are tempered glass or laminated glass
). But I wouldn't mind something that is always on me and I have no more room in my pants for additional gadgets!