Flicker Example
If you use motion or animation, make sure that it's necessary.
Avoid causing the screen to flicker; large flickering or flashing images may cause seizures in users with photosensitive epilepsy. These seizures can be triggered by flickering or flashing in the 4 to 59 flashes per second (Hertz) range, with greatest sensitivity occurring at 20 flashes per second. Rapid tonal changes can have the same effect.
Technique to Avoid
Moving text and animation can be distracting. Individuals with visual impairments or cognitive disabilities and some screen readers may not be able to read moving text. Rapid tonal changes or large flickering images can cause seizures. |
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