The intent of this Success Criterion is to allow users to prevent animation from being displayed on Web pages. Some users experience distraction or nausea from animated content. For example, if scrolling a page causes elements to move (other than the essential movement associated with scrolling) it can trigger vestibular disorders. Vestibular (inner ear) disorder reactions include dizziness, nausea and headaches. Another animation that is often non-essential is parallax scrolling. Parallax scrolling occurs when backgrounds move at a different rate to foregrounds. Animation that is essential to the functionality or information of a web page is allowed by this Success Criterion.
"Animation from interactions" applies when a user’s interaction initiates non-essential animation. In contrast, 2.2.2 Pause, Stop, Hide applies when the web page initiates animation.
Note: The impact of animation on people with vestibular disorders can be quite severe. Triggered reactions include nausea, migraine headaches, and potentially needing bed rest to recover.
How can a website reduce the chances of triggering a vestibular disorder? Choose any one of the following solutions. Avoid using unnecessary animation. Provide a control for users to turn off non-essential animations from user interaction. Take advantage of the reduce motion feature in the user-agent or operating system.
What about movement caused by a user scrolling a page? Moving new content into the viewport is essential for scrolling. The user controls the essential scrolling movement so it is allowed. Only add non-essential animation to the scrolling interaction in a responsible way. Always give users the ability to turn off unnecessary movement.