Fix flexbox display for Firefox
Fix flexbox display for Firefox

klausbayrhammer/BackstopJS,garris/BackstopJS,garris/BackstopJS,mirzazeyrek/BackstopJS,mirzazeyrek/BackstopJS,garris/BackstopJS,cookchristopher/BackstopJS,klausbayrhammer/BackstopJS,cookchristopher/BackstopJS