2.27 Avoid deprecated features of W3C technologies
Contents
WAI checkpoint 11.2
Full WAI text: "Avoid deprecated features of W3C technologies." A "deprecated" feature is one which the W3C wants to remove from the official standard for a given technology but which has not yet become officially obsolete or removed. Even though they are part of the official standard, the W3C discourages the use of deprecated features. For example, the "font" tag in HTML is an example of a deprecated feature in HTML 4.0.
Rationale
The World Wide Web Consortium (W3C) is an independent, international body that creates Internet and programming language standards. Its recommendations and standards are highly regarded.
W3C technologies are continually reviewed for accessibility so that the latest versions may have discarded some features which have been found to hinder accessibility. By using a current W3C technology, you are more likely to embed accessibility in your website.
Directions and Techniques
Consult the W3C list of HTML elements and attributes
The index of HTML elements and attributes lists all elements in HTML 4.0. Deprecated elements are indicated with an asterisk.
Write Cascading Style Sheets (CSS) which support user override of styles
Users can override CSS with their own style sheets, which may be configured to suit their needs. This is an important feature of CSS and should be provided. See the WAI recommended techniques for user override of styles.
Avoid using deprecated features for presenting fonts
See the WAI recommended techniques for specifying font styles.
How you could check for this:
Test with the W3C HTML validator
The W3C HTML validator can check HTML to ensure that it validates to formal grammars. The W3C also provide a comprehensive list of the formal grammars which it uses. Some authoring tools also include validators. If you use an authoring tool, you should ensure that the validator is up to date and validates for deprecated features.
Guidelines for Web Accessibility - Priority 2- 2.1 Ensure that images have sufficient contrast for people with colour deficient vision
- 2.2 Avoid causing content to blink
- 2.3 Avoid movement in content
- 2.4 Ensure that dynamic content is accessible or provide an alternative presentation or page
- 2.5 Use style sheets to control layout and presentation
- 2.6 Use relative rather than absolute units
- 2.7 Use header elements to convey structure
- 2.8 Break up large blocks of information where appropriate
- 2.9 Ensure that information laid out using tables make sense when linearised, or provide an alternative equivalent
- 2.10 Do not use structural mark-up to format information laid out using tables
- 2.11 Describe the purpose of frames and how they relate to each other if it is not obvious by their titles alone
- 2.12 Clearly identify the target of each link
- 2.13 Provide information about pages and sites in metadata
- 2.14 Provide information about the general layout of a site
- 2.15 Use navigation mechanisms consistently
- 2.16 Associate labels explicitly with their controls
- 2.17 Properly position the labels of form controls
- 2.18 Ensure that user interfaces are device-independent
- 2.19 Use logical event handlers in scripts
- 2.20 Use input device-independent event handlers in scripts and applets
- 2.21 Ensure that scripts and applets are accessible
- 2.22 When an appropriate markup language exists, use markup rather than images to convey information
- 2.23 Create documents that validate to published formal grammars
- 2.24 Mark up lists and list items using the proper HTML tags
- 2.25 Use quotation mark-up for quotations, but not for formatting
- 2.26 Where possible, use appropriate W3C technologies of the latest supported versions
- 2.27 Avoid deprecated features of W3C technologies
- 2.28 Do not periodically auto-refresh pages
- 2.29 Do not use mark-up to redirect pages automatically
- 2.30 Do not generate pop-ups or other windows and do not change the current window without informing the user
