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"4.1/headings-order" in axe html 4.1.

List of Axe HTML 4.1 rules

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  1. <audio> elements must have a captions <track>
  2. <blink> elements are deprecated and must not be used
  3. <dl> elements must only directly contain properly-ordered <dt> and <dd> groups, <script>, or <template> elements
  4. <dt> and <dd> elements must be contained by a <dl>
  5. <html> element must have a lang attribute
  6. <html> element must have a valid value for the lang attribute
  7. <html> elements with lang and xml:lang must have the same base language
  8. <li> elements must be contained in a <ul> or <ol>
  9. <marquee> elements are deprecated and must not be used
  10. <object> elements must have alternate text
  11. <ul> and <ol> must only directly contain <li>, <script> or <template> elements
  12. <video> elements must have a <track> for captions
  13. <video> elements must have an audio description <track>
  14. accesskey attribute value must be unique
  15. Active <area> elements must have alternate text
  16. All <th> elements and elements with role="columnheader" or role="rowheader" must have data cells they describe
  17. All cells in a <table> element that use the headers attribute must only refer to other cells of that same <table>
  18. All non-empty <td> elements in tables larger than 3 by 3 must have an associated table header
  19. All page content must be contained by landmarks
  20. All text elements must have sufficient contrast between text in the foreground and background colors behind it in accordance with WCAG 2 AAA contrast ratio thresholds.
  21. Anchors must only be used as links with valid URLs or URL fragments
  22. ARIA attributes must conform to valid names
  23. ARIA attributes must conform to valid values
  24. ARIA button, link, and menuitem must have an accessible name
  25. ARIA dialog and alertdialog must have an accessible name
  26. ARIA input fields must have an accessible name
  27. ARIA meter must have an accessible name
  28. ARIA progressbar must have an accessible name
  29. ARIA role must be appropriate for the element
  30. ARIA roles used must conform to valid values
  31. ARIA toggle fields have an accessible name
  32. ARIA tooltip must have an accessible name
  33. ARIA treeitem must have an accessible name
  34. aria-hidden elements do not contain focusable elements
  35. aria-hidden="true" must not be present on the document <body>
  36. Audio must have controls that provide users with the ability to stop automatically played audio after three seconds
  37. Autocomplete attribute must be used correctly
  38. Banner landmark must not be contained in another landmark
  39. Bold, italic text and font-size are not used to style <p> elements as a heading
  40. Buttons must have discernible text
  41. Certain ARIA roles must be contained by particular parent elements
  42. Certain ARIA roles must contain particular children
  43. Checkbox inputs with the same name attribute value must be part of a group
  44. Complementary landmarks and/or asides are top level
  45. Contentinfo landmark must not be contained in another landmark
  46. CSS Media queries are not used to lock display orientation
  47. Data or header cells should not be used to give caption to a data table
  48. Documents must contain a title element to aid in navigation
  49. Elements containing role="img" have an alternative text
  50. Elements in the focus order need a role appropriate for interactive content
  51. Elements must only use allowed ARIA attributes
  52. Elements should not have tabindex greater than zero
  53. Elements whose role is none or presentation must not conflict with other roles
  54. Ensure that links with the same accessible name serve a similar purpose
  55. Ensure that scrollable region has keyboard access
  56. Ensures <frame> and <iframe> elements with focusable content do not have tabindex=-1
  57. Ensures role="text" is used on elements with no focusable descendants
  58. Ensures table headers have discernible text
  59. Ensures the document has at most one main landmark
  60. Form <input> elements must have labels
  61. Form <input> elements should have a visible label
  62. Form fields do not have duplicate labels
  63. Frames must be tested with axe-core
  64. Frames must have a unique title attribute
  65. Frames must have title attribute
  66. Heading levels should only increase by one
  67. Headings must not be empty
  68. Hidden content on the page cannot be analyzed
  69. ID attribute value must be unique
  70. ID attribute values must be unique
  71. IDs used in ARIA and labels must be unique
  72. Image buttons must have alternate text
  73. Images must have alternate text
  74. Inline text spacing must be adjustable with custom stylesheets
  75. Input buttons must have discernible text
  76. Label and name from content mismatch
  77. Landmarks must have a unique role or role/label/title (i.e. accessible name) combination
  78. lang attribute must have a valid value
  79. Layout tables must not use data table elements
  80. Links must be distinguished from surrounding text in a way that does not rely on color
  81. Links must have discernible text
  82. Main landmark must not be contained in another landmark
  83. Nested interactive controls are not announced by screen readers
  84. Page must contain a level-one heading
  85. Page must have means to bypass repeated blocks
  86. Page must have one main landmark
  87. Page must not have more than one banner landmark
  88. Page must not have more than one contentinfo landmark
  89. Radio inputs with the same name attribute value must be part of a group
  90. Required ARIA attributes must be provided
  91. Scope attribute should be used correctly on tables
  92. select element must have an accessible name
  93. Server-side image maps must not be used
  94. SVG images and graphics require accessible text
  95. Text elements must have sufficient color contrast against the background
  96. Text of buttons and links should not be repeated in the image alternative
  97. The <caption> element should not contain the same text as the summary attribute
  98. The skip-link target should exist and be focusable
  99. Timed refresh must not exist
  100. Unsupported DPUB ARIA roles should be used on elements with implicit fallback roles
  101. Use aria-roledescription on elements with a semantic role
  102. Users should be able to zoom and scale the text up to 500%
  103. Zooming and scaling must not be disabled

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