Technique F50:Failure of Success Criterion 2.2.2 due to a script that causes a blink effect without a mechanism to stop the blinking at 5 seconds or less

Description

Scripts can be used to blink content by toggling the content's visibility on and off at regular intervals. It is a failure for the script not to include a mechanism to stop the blinking at 5 seconds or earlier. See SCR22: Using scripts to control blinking and stop it in five seconds or less for information about how to modify the technique to stop the blinking.

Examples

Example 1

The following example uses script to blink content, but the blink continues indefinitely rather than stopping after five seconds.

...
<script type="text/javascript">
<!--
// blink "on" state
function show()
{
	if (document.getElementById)
	document.getElementById("blink1").style.visibility = "visible";
	settime-out("hide()", 450);
}
// blink "off" state
function hide()
{
	if (document.getElementById)
	document.getElementById("blink1").style.visibility = "hidden";
	settime-out("show()", 450);
}
// kick it off
show();
//-->
</script>
...
<span id="blink1">This content will blink</span>

Applicability

Technologies that support script-controlled blinking of content.

Tests

Procedure

For each instance of blinking content:

  1. Determine if the blinking stops in 5 seconds or less.

Expected Results

If #1 is false, then the content fails the Success Criterion.

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