"Canopy breakers" are different from the automotive "window breakers" in that the surfaces to be destroyed are also quite different. Automotive glass is tempered, meaning the entire surface is under a manufactured strain. It is quite durable and strong, but, because of the inherent stresses induced in the manufacturing process, it is susceptible to a sharp blow from a pointed object. Thus, a window breaker can (when properly used) shatter the entire surface into small chunks that pose minimal risk to occupants of the vehicle and allow for escape through the window frame.

Plexiglass glider canopies (as well as many other aviation windows) are much more flexible, and do not incorporate the tempered glass internal structure, Beating on the inside of a plastic canopy with the tiny pointed hammer that does so well on tempered glass is a basic exercise in futility, especially if the canopy has been partially broken, say, after a crash. There are specially designed tools that are intended for use with plastic canopies, like this one:

https://www.flyboyaccessories.com/Ch...ker-p/2201.htm