Notifies users of content that is hidden and unable to be checked for accessibility issues.
It is impossible to automatically check hidden content for accessibility rules breaches.
Screen reader users and sighted people must both be able to view visually hidden content. When content needs to be hidden from seeing users for a compelling reason, it is typically also necessary to hide it from blind users for the same reason. Making the content accessible to blind users makes sense when it is already available to sighted users.
When the CSS values display: none or visibility: hidden are used, content will be hidden from screen reader users (and all sighted users as well). The items become accessible to screen reader users when CSS properties are changed to display: block, display: inline, or other display values.
What this Accessibility Rule Checks
Checks for the presence of the hidden item content CSS style property values of display: none and visibility: hidden, and notifies users of their presence.