Review cursor

A screen reader user has more than one cursor. There is the system focus, the one the application knows about, and there is a review cursor that walks the screen independently of it. NVDA calls it the review cursor, VoiceOver on macOS reaches the same idea through the VoiceOver cursor, and Orca and the Android and iOS readers call the flattened version of it flat review. The point of the second cursor is that reading is not interaction. A person typing in a message field can send the review cursor up to re-read the error above the form, out to the status line, or across to a toolbar label, and come back to find the caret exactly where they left it and the application none the wiser.

That independence is what makes it a design constraint rather than a piece of trivia. Content that no tab stop ever visits is still read: a timestamp, a helper line, a count in the corner, the text inside an inert region that has been made unreachable for interaction but is still painted on the screen. So text on screen is text somebody can find, which cuts both ways. It rescues information you forgot to make reachable, and it exposes leftovers you thought were invisible because nothing could focus them.

Three neighbouring words get swapped for each other and they name three different things. Browse mode is the reading mode itself, where the reader takes the keyboard and moves through a document with single keys instead of operating controls. The rotor is the dial that chooses what kind of element the next gesture visits, headings or links or form controls. A review cursor is neither a mode nor a filter: it is a second pointer that reads whatever is under it without telling the application anything happened.

The practical consequence is that a screenshot is not the boundary of your interface for a screen reader user, and neither is the tab order. If a label only makes sense next to the control it belongs to, someone will read it on its own. If a status only makes sense as an update, someone will find it a minute later sitting there as plain text. Writing every string so it survives being read alone is the same discipline that makes a good accessible name, applied to the parts nobody bothers to name.