Hi,
There seems to be a problem with the JavaScript in stripeconect_end.php
The var additionalData is not working and blocking the execution.
By replacing
stripe.createToken(card, additionalData).then(function(result) {
by
stripe.createToken(card).then(function(result) {
Now it submits the form, however now I can see a problem in the Stripe logs:
1.Creates the token OK
2. Creates the customer OK
3. Fails when creating the charge, as follows:
{
  "error": {
    "code": "missing",
    "doc_url": "https://stripe.com/docs/error-codes/missing",
    "message": "Cannot charge a customer that has no active card",
    "param": "card",
    "type": "card_error"
  }
}
please help, thanks!