When utilizing the custom survey option, the customer is sent the link in email. This sends them to the SWSD and requires a login. The least amount of extra clicks as possible would be beneficial in getting our customers to complete the survey.
I was informed that this is not a feature yet. If you use SSO, we got around this by having users log into the portal site at least once to have SWSD see a trigger 'login", confirmed their default http/https protocol is set to their default browser and this allowed them to take surveys without seeing that login prompt moving forward. Its a lot of steps but it worked for us until we find a better alternative.