Cascading Style Sheets.
CSS defines the blink value for the text-decoration property. When used, it causes any text in elements with this property to blink at a predetermined rate. This cannot be interrupted by the user, nor can it be disabled as a user agent preference. The blinking continues as long as the page is displayed. Therefore, content that uses text-decoration:blink fails the Success Criterion because blinking can continue for more than five seconds.
A product list page uses the text-decoration:blink style on an element to draw attention to sale prices. This fails the Success Criterion because users cannot control the blink.
<p>My Great Product <span style="text-decoration:blink">Sale! $44,995!</span></p>
blink.