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- iframes that convey content to users MUST have a non-empty title attribute.
- The iframe title MUST be accurate and descriptive.
- Frames MUST have a unique title (in the context of the page).
- The source page of an iframe MUST have a valid, meaningful <title>.
Other (content)
- Critical strikethrough text MUST be supplemented with a text-based method to convey the meaning of the strikethrough.
- Critical text designated for insertion MUST be supplemented with a text-based method to convey the meaning of the insertion.