Rocket Validator automatically checks your pages on the W3C Validator.
HTML issues tagged as aria-controls.
aria-controls attribute identifies an element or elements in the same document whose contents or presence are controlled by the current element. It must point to existing elements by their ID. Check that the IDs contained in that property exist within the same document.
ARIA can express semantic relationships between elements that extend the standard parent/child connection, such as a custom scrollbar that controls a specific region, for example:
<div role="scrollbar" aria-controls="main"></div> <div id="main"> . . . </div>
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