Finally I ended using (it's also working for different languages of Recaptcha challenges) if someone searches for the same:
">CSS>iframe[src^=' https://www.google.com/recaptcha/api2/bframe ']>FRAME> >CSS>#recaptcha-verify-button"
Use RESET option in BROWSER TAB . this will clear cookies but cache will be still present. You can also make a profile and save it for further use. Let us know if this works for you.