holmes

The Holmes module is an adaptation of Holmes - The CSS Markup Detective, which describes itself as "a stand-alone diagnostic CSS stylesheet that can highlight potentially invalid, inaccessible or erroneous HTML(5) markup by adding one class." In addition to highlighting markup issues, Holmes makes clever use of CSS to display messages about the specific issues with the highlighted markup. You can find a full test suite of what Holmes can do here.

The Holmes module includes all the Holmes CSS and does all the work to integrate seamlessly with Drupal, providing accessibility validation at the click of a button. The Holmes module includes the following features:

• Permission-based access to Holmes debugging
• A simple button to toggle Holmes debugging on any page
• Ability to display Holmes debugging information by default on any page using the query parameter holmes-debug=true