URGENT : Stripe.js token was not passed! Report this message to the site administrator. (on civicrm 4.7.20)
Please upgrade to the current github 4.7-dev version. Lots of work went into eliminating "Stripe.js token not passed!" errors that can for a variety of reasons. Jacques-Marie, you can reap the benefits of this labor by upgrading.  

You already posted the url, but this is it:

https://github.com/drastik/com.drastikbydesign.stripe