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Fix the markup the warning points to, but keep the element’s meaning and expected behavior intact. Start with the first structural error, inspect its surrounding source, make a small correction, and rerun the checker. A clean validation or lint report is useful evidence—not proof that a page is accessible.
Start by checking the right artifact
First identify what the tool analyzed: authored HTML, the rendered page, or JSX source. A JSX accessibility lint rule examines recognizable patterns in JSX; it does not replace checking the HTML that the browser receives. If a template or component generates the page, inspect the relevant output as well as the source that produced it.
HTML conformance checkers and JSX accessibility lint rules address different layers. For example, the Nu Html Checker and the W3C Markup Validation Service check HTML conformance, while eslint-plugin-jsx-a11y provides static accessibility rules for JSX. They can complement one another; the available documentation does not establish a comparative accuracy ranking.
Use a repair loop that limits guesswork
- Read the first reported error. Treat its line and column as a pointer, then inspect the surrounding tags, attributes, and nesting. Earlier malformed markup can confuse parsing of what follows, so later messages may be cascades rather than independent faults.
- Correct the earliest structural problem. Check the document declaration, element nesting, end-tag requirements, attributes, and content model involved. Do not delete a flagged element or attribute without confirming what rule it violates.
- Rerun the same check. Fix a small group of related issues, then validate again. This helps distinguish resolved messages from new ones and prevents a large cleanup from obscuring the cause.
- Check meaning and behavior in context. Confirm that the corrected structure still represents the content, relationships, and interactions people need. Review the page manually as well as reading the report.
The Nu Html Checker explains the purpose of conformance checking this way: “The core reason to run your HTML documents through a conformance checker is simple: To catch unintended mistakes—mistakes you might have otherwise missed, so that you can fix them.”
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Keep semantic elements instead of silencing the warning
Choose HTML elements for what they mean, not merely how they look. Headings should express heading structure, lists should remain lists, navigation destinations should be links, and actions should be buttons. Associate form labels with their controls. Replacing meaningful elements with generic div containers, or adding role="presentation" just to quiet a rule, can discard useful structure rather than repair the underlying issue.
W3C WAI describes the objective of its G115 technique as “to mark up the structure of the web content using the appropriate semantic elements.” WAI techniques are informative examples of ways to meet WCAG; they are not the only permitted methods.
Choose a native control for the interaction
Use a link for navigation
An anchor represents a hyperlink to a meaningful destination. If the element has no meaningful destination, reconsider whether it should be an anchor. For an action—such as submitting a form or opening a dialog—a button is generally the appropriate native control.
Use a button for an action
A clickable div or other static element does not become an accessible control simply because it has a click handler or an ARIA role. Native anchors and buttons provide different keyboard behavior: an anchor is expected to activate with Enter; a button activates with Enter and Space. If a custom role is genuinely necessary, implement focusability and the expected keyboard behavior too; the role alone supplies neither.
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Repair Windows errors before they cause bigger problemsFix Now →Scan for outdated or missing drivers - takes under a minuteDriver Scan →The no-static-element-interactions rule documentation covers static elements with interaction handlers. It also recognizes a justified exception where a parent only captures bubbled events from accessible child controls; explain the reason when using such an exception rather than disabling the rule without context.
Handle common reports without removing useful structure
Missing or malformed DOCTYPE
For an ordinary HTML document, W3C Markup Validator help recommends the generic <!DOCTYPE html> declaration. Correct a malformed declaration early, then rerun validation because it can affect how later markup is parsed.
Misnested or improperly closed elements
Check the required nesting and whether each element requires, permits, or forbids an end tag. Invalid structure can affect how assistive technologies interpret a page. WAI’s H74 technique discusses markup errors, including incorrect tag use, as a possible source of parsing problems.
Duplicate IDs or attributes
Inspect the relevant component and its generated page, not just the line flagged in a source file. IDs need to be unique where they identify elements, and duplicate attributes should be resolved rather than hidden. WAI H74 addresses unique IDs and correct tag use; its related parsing guidance also includes duplicate attributes.
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Invalid anchor use
An anchor should communicate a real hyperlink destination. If the intended behavior is an action rather than navigation, use a button instead of making a link imitate one. See the anchor-is-valid rule documentation for the JSX lint rule.
Suggested automatic cleanup
W3C validator help describes HTML-Tidy cleanup output but cautions that there are no guarantees about validity or other aspects of the result. Review generated edits, especially changes to element types, relationships, and interaction behavior, before accepting them.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.What a clean report can—and cannot—tell you
Validation is useful for finding unintended markup mistakes, and linting can flag accessibility patterns that are statically recognizable. Neither establishes by itself that content has meaningful labels and relationships or that interactions work for users. WAI describes validation as a useful technique, while its documented techniques remain examples rather than a complete accessibility assessment.
Quick Recap
- Use an HTML checker for conformance issues in the HTML artifact and JSX lint rules for applicable JSX authoring patterns.
- Fix early structural errors first, then rerun the relevant checks.
- Review semantics, labels, relationships, focus, and keyboard behavior in the actual page.
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