Accessibility Checker is a function within Open Author usable to instantly identify any accessibility issues and solve any issues that are found. It identifies and reports instances where content lacks proper color contrast, font size, and alternative text, etc. This will ensure that everyone is able to access the content, including those who use screen readers and screen magnifiers.
Use the Accessibility Checker function by clicking the Check Accessibility () toolbar button. Accessibility Checker will then perform its checking process and display results. If there are any accessibility issues, they will be displayed one at a time to either be ignored (leave as-is) or solved. A Quick-Fix feature can be used to solve issues, or they can be manually changed.
More in-depth information on how to use the Accessibility Checker can be found here: https://ckeditor.com/docs/ckeditor4/latest/features/accessibility_checker.html