7.1 Modern Support

Websites must utilize HTML5 and work on modern browsers.

7.2 Structure & Layout

Websites must not use tables as the primary means of site structure of layout.

7.3 External Stylesheets

Websites must utilize external CSS stylesheets for styling.

Best Practices

While the use of inline styles can sometimes be necessary, excessive use of inline styles is not permitted.

7.4 Favicons

Websites must provide at least a 16px by 16px favicon.

7.5 Development Environments & Resources

Websites not under development must not serve assets such as images, CSS, and Javascript from development environments.

7.6 Flash

Websites must not use Flash.

Security Vulnerabilities & End-of-Life

Not only does Flash have numerous security vulnerabilities, Adobe, in collaboration with large web and computer companies, will stop updating and distributing Flash Player by the end of 2020.

For more information regarding Flash's end-of-life, check out Adobe's Flash & The Future of Interactive Content article.