What the standard says
All functionality that uses multipoint or path-based gestures for operation can be operated with a single pointer without a path-based gesture, unless a multipoint or path-based gesture is essential.
Why it matters
Pinch, swipe-along-a-path and two-finger rotate are impossible for people using a head pointer, a switch, or one hand.
What a failure looks like
- failsA map that only zooms by pinching.
- failsA slider that only responds to a drag.
How to fix it
- doAdd plain buttons alongside the gesture: zoom in / zoom out, previous / next.
How A11ySignal checks it
manual
No automated rule can judge this criterion, and we will not pretend otherwise. A clean scan does not mean 2.5.1 passes — it means nothing we can measure fails. This one needs a person.