Three Flashes

Understanding WCAG2.0

It is the same as 2.3.1, except that exceptions are not allowed. If 2.3.1a is met, it may be considered conforming, but this judgment is strict, please be careful as even 1 pixel size is not allowed.

Principle Operable User interface components and navigation must be operable.
Guideline Seizures Do not design content in a way that is known to cause seizures.
Criterion Three Flashes
(2.3.2 AAA)
Web pages do not contain anything that flashes more than three times in any one second period.

URL of Techniques for WCAG 2.0