eshop

Hi, I have a problem with my site in test http://www.jolimentronde.com
On google chrome I can validate command but when I want to conclude transaction and validate address informations, the submit button is not here. On firefox, when I valid command the address field don’t appear as well as the submit button. Sometimes it reappear, I can’t understand what’s going on and how I can solve the problem. I use wordpress 3.8.1–fr_FR and eshop 6.3.11. Thanks to help me please.

https://ww.wp.xz.cn/plugins/eshop/