Failure of Success Criterion 2.1.2 and Conformance Requirement 5 due to combining multiple content formats in a way that traps users inside one format type

ID: F10

Technology: failures

Type: Failure

When to Use

Applies when content creates a situation where the user can enter the content using the keyboard, but cannot exit the content using the keyboard.

Description

When content includes multiple formats, one or more user agents or plug-ins are often needed in order to successfully present the content to users. For example, a page that includes HTML, SVG, SMIL and XForms may require a browser to load as many as three different plug-ins in order for a user to successfully interact with the content. Some plug-ins create a common situation in which the keyboard focus can become "stuck" in a plug-in, leaving a keyboard-only user with no way to return to the other content.

Examples

A plug-in traps the user: A user tabs into a plug-in and is unable to return to content outside the plug-in content with the keyboard. The user has to restart their browser in order to regain control and navigate to a new page and is unable to access any content that appears beyond the plug-in content.

Tests

Procedure

Using a keyboard, navigate through the content.
Check to see that the keyboard focus is not "trapped" and it is possible to move keyboard focus out of the plug-in content without closing the user agent or restarting the system.

Expected Results

If the keyboard focus becomes "trapped," then this failure condition applies and content fails the Success Criterion and conformance requirement 5.