In general, reviewers do not need to log in when leaving feedback. However, if the reviewer has signed up for Filestage in the past and is using the same email address to leave a comment, they will be prompted to sign-in. This is for security reasons as we do not want someone leaving comments on a registered account that may not be their own!
To make it so the reviewer does not have to log in, you have a few options:
Have the reviewer email us at firstname.lastname@example.org and ask to delete their account. By deleting their account, they will no longer be prompted to log in. This is typically the easiest solution. (note: for security reasons, she will have to email me from the email she signed up with)
You can turn off reviewer email notifications in the reviewer settings and they won't be asked to log in. (Note - then your reviewers will not get any email notifications)
Ask your reviewers to use a different email address (it could be as simple as email@example.com)
Have them reset their password, so they can leave comments (https://app.filestage.io/#!/password/forgot)
Let us know if you have any questions by reaching out to us on chat or emailing us at firstname.lastname@example.org We're always happy to help!