| 1 | 6 | www.udemy.com | 2 | 1 | meta-refresh | Ensure <meta http-equiv="refresh"> is not used for delayed refresh |  |
| 1 | page-has-heading-one | Ensure that the page, or at least one of its frames contains a level-one heading |  |
| 2 | 8 | www.chegg.com | 2 | 1 | landmark-one-main | Ensure the document has a main landmark | |
| 1 | page-has-heading-one | Ensure that the page, or at least one of its frames contains a level-one heading | |
| 3 | 9 | www.khanacademy.org | 2 | 1 | landmark-one-main | Ensure the document has a main landmark | |
| 1 | page-has-heading-one | Ensure that the page, or at least one of its frames contains a level-one heading | |
| 4 | 5 | www.blackboard.com | 2 | 2 | color-contrast | Ensure the contrast between foreground and background colors meets WCAG 2 AA minimum contrast ratio thresholds |  |
| 1 | heading-order | Ensure the order of headings is semantically correct | |
| 5 | 3 | quizlet.com | 3 | 2 | color-contrast | Ensure the contrast between foreground and background colors meets WCAG 2 AA minimum contrast ratio thresholds | |
| 1 | meta-refresh | Ensure <meta http-equiv="refresh"> is not used for delayed refresh | |
| 2 | region | Ensure all page content is contained by landmarks | |
| 6 | 2 | www.duolingo.com | 4 | 1 | color-contrast | Ensure the contrast between foreground and background colors meets WCAG 2 AA minimum contrast ratio thresholds | |
| 8 | image-alt | Ensure <img> elements have alternative text or a role of none or presentation | |
| 1 | landmark-unique | Ensure landmarks are unique | |
| 1 | meta-viewport | Ensure <meta name="viewport"> does not disable text scaling and zooming | |
| 7 | 10 | www.edx.org | 4 | 1 | button-name | Ensure buttons have discernible text | |
| 35 | color-contrast | Ensure the contrast between foreground and background colors meets WCAG 2 AA minimum contrast ratio thresholds | |
| 1 | page-has-heading-one | Ensure that the page, or at least one of its frames contains a level-one heading | |
| 1 | scrollable-region-focusable | Ensure elements that have scrollable content are accessible by keyboard | |
| 8 | 7 | www.scribd.com | 5 | 1 | button-name | Ensure buttons have discernible text | |
| 77 | color-contrast | Ensure the contrast between foreground and background colors meets WCAG 2 AA minimum contrast ratio thresholds | |
| 1 | landmark-unique | Ensure landmarks are unique | |
| 2 | region | Ensure all page content is contained by landmarks | |
| 2 | svg-img-alt | Ensure <svg> elements with an img, graphics-document or graphics-symbol role have an accessible text | |
| 9 | 1 | www.instructure.com | 6 | 2 | aria-allowed-attr | Ensure an element's role supports its ARIA attributes | |
| 2 | aria-required-children | Ensure elements with an ARIA role that require child roles contain them | |
| 5 | aria-required-parent | Ensure elements with an ARIA role that require parent roles are contained by them | |
| 9 | color-contrast | Ensure the contrast between foreground and background colors meets WCAG 2 AA minimum contrast ratio thresholds | |
| 2 | heading-order | Ensure the order of headings is semantically correct | |
| 10 | presentation-role-conflict | Elements marked as presentational should not have global ARIA or tabindex to ensure all screen readers ignore them |  |
| 10 | 4 | www.coursera.org | 6 | 138 | color-contrast | Ensure the contrast between foreground and background colors meets WCAG 2 AA minimum contrast ratio thresholds | |
| 1 | landmark-contentinfo-is-top-level | Ensure the contentinfo landmark is at top level | |
| 1 | landmark-no-duplicate-contentinfo | Ensure the document has at most one contentinfo landmark | |
| 2 | landmark-unique | Ensure landmarks are unique | |
| 2 | nested-interactive | Ensure interactive controls are not nested as they are not always announced by screen readers or can cause focus problems for assistive technologies | |
| 1 | scrollable-region-focusable | Ensure elements that have scrollable content are accessible by keyboard | |
