Techniques for WCAG 2.0

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F61: Failure of Success Criterion 3.2.5 due to complete change of main content through an automatic update that the user cannot disable from within the content

Applicability

General

This failure relates to:

Description

This document describes a failure that occurs when the content in the main viewport viewport is automatically updated, and there there is no option for a user to disable this behavior.

Two procedures are presented below to test for the existence of a failure against Success Criterion 3.2.5. Procedure 1 is the preferred procedure and assumes that content authors have access to the code that generates the viewport content.

However there may be instances where this may not be possible (eg: in certain content management systems, application environments such as django or ruby-on-rails, or content generated through scripting languages such as AJAX or PHP that are generated by third parties.) To that end, the second procedure is supplied to allow testing in these instances. Note that timeframes are indicative only, and that any change after any amount of time should be treated as a failure if the test otherwise does not pass the other step evaluations.

Examples

Failure Example 1:

A news site automatically refreshes itself to ensure that it has the newest headlines. There is no option to disable this behavior.

Failure Example 2:

A slideshow fills the entire viewport and advances to the next slide automatically. There is no stop button.

Failure Example 3:

A search engine automatically generates results and dynamically updates content based on user input. There is no option to disable this behavior.

Resources

Resources are for information purposes only, no endorsement implied.

(none currently listed)

Tests

Procedure

  1. Open the source code in an appropriate editing tool.

  2. Examine the source code thoroughly.

  3. Confirm that content is dynamically generated or the code will trigger a change of context for the viewport on an event or after a time period.

  4. Confirm that there does not exist an appropriate mechanism for users to disable this behavior.

Expected Results

Tests

Procedure

  1. Open the content in the viewport.

  2. Leave the content open for a length of time 10 times what a user could reasonably be expected to keep the viewport open for. For instance, a site's web analytics may indicate that average user visits last 1 hour and most return users visit once per day. 24 hours could be considered an appropriate length of time for the procedure.

  3. Check if there has been a change in context during this time.

  4. Confirm that the content does not contain a mechanism by which to disable automatic changes.

Expected Results

Note: Regardless of the time span used at step 2 of the procedure, if step 3 tests true after any length of time, then step 4 must be confirmed and the expected results evaluated as at 1.