"To crack the glass" means to break or damage something, especially a barrier or limitation, in order to achieve a particular goal or outcome. Full definition
She was among a handful of woman painters of her generation — roughly that which emerged in the 1970s — who cracked the glass ceiling of the art hierarchy. (questia.com)
Again, if this is too much for you, don't crack that glass back panel or you may have to live with it. (nashvillechatterclass.com)
We also really love the thermal shock resistance because you don't have to worry as much about going from hot to cold and back again because it won't crack the glass. (geekwrapped.com)