Rocket Validator integrates the W3C Validator HTML checker into an automated web crawler.
HTML issues tagged as unquoted.
Attribute values for HTML elements must be enclosed within quotes. Check for attributes whose values are missing quotes.
<!-- These are invalid --> <div class=important></div> <div class=important"></div> <!-- This is valid --> <div class="important"></div>
When was the last time you validated your whole site?
Keep your sites healthy checking for A11Y/HTML issues on an automated schedule.