Content flashes more than 3 times per second below threshold
A page MUST NOT contain content that flashes more than 3 times per second.
Flashing or strobe-type effects in videos, graphics, or animations can put some people — those with photosensitive epilepsy — at risk for seizures. To be on the safe side, you should consider eliminating ALL flashes. However, small flash areas or very low contrast flashes may be acceptable from a seizure perspective, even though they are still likely to be annoying and distracting, which can be an issue for people with attention deficit disorders or cognitive disabilities.
Fix this issue by ensuring that no content on the screen flashes more than 3 times per second.