Contact Form 7: thank you page call with on_sent_ok does not work

I have updated to the new WP version and also Contact Form 7 3.8.1.
The call to the thank you page with:

on_sent_ok: “location.replace(‘/availability-thankyou.html’);

which I put into the additional settings field worked fine until this last update. Now after submitting the form ok button only the standard message sent alert (in green) shows.

Any hints?

I am also using the wpml multilingual cms plugin in the newest version 3.1.5.

Thank you.