Assessing Suspicious Emails with Banner Warnings Among Blind and Low-Vision Users in Realistic Settings

Warning users about suspicious emails usually happens through visual interventions such as banners. Evidence from laboratory experiments shows that email banner warnings are unsuitable for blind and low-vision (BLV) users as they tend to miss or make no use of them. However, the laboratory settings preclude a full understanding of how BLV users would realistically behave around these banner warnings because the experiments don't use the individuals' own email addresses, devices, or emails of their choice. To address this limitation, we devised a study with n=21 BLV email users in realistic settings. Our findings indicate that this user population misses or makes no use of Gmail and Outlook banner warnings because these are implemented in a "narrow" sense, that is, (i) they allow access to the warning text without providing context relevant to the risk of associated email, and (ii) the formatting, together with the possible actions, is confusing as to how a user should deal with the email in question. To address these barriers, our participants proposed designs to accommodate the accessibility preferences and usability habits of individuals with visual disabilities according to their capabilities to engage with email banner warnings.