The return page should redirect automatically

Problem/Motivation

Currently, when returning from Mollie, you land on a page stating the payment status was not yet received (I can imagine this might not happen when the return callback from Mollie happens to out-race the redirect back to the site, but I have not witnissed that yet). The user is asked to click a link to see if the status has been updated yet (when everything is working well, it will be and you land on Commerce's payment confirmation page.

This is not very user friendly (and the page doesn't look very pretty either).

Proposed resolution

Do several things:

• Poll using JavaScript to see if the payment was confirmed yet
  • Do this for a maximum amount of time, show a message stating something like "This is taking longer than usual. Please contact the site administrator and refer your order ID %order_id."
• Show a title (e.g. "Waiting for Mollie")
• Change the message to something like "We are waiting for confirmation from Mollie. If you are not redirected automatically, click here."
• Show the throbber after the message, to indicate activity.

Remaining tasks

• Agree on desired change
• Build
• Review
• Merge

User interface changes

See proposed resolution.

API changes

None.

Data model changes

None.