HTML Checking for Large Sites
Rocket Validator automatically scans your sites for accessibility issues using the W3C Validator,
hosted on our own servers and integrated into our web crawler.
HTML issues tagged as touchstart.
The ontouchstart attribute, used in devices with a touch screen, and not supported by all browsers, is not a valid attribute in the current HTML5 standard.
You can consider replacing it with the more generic onclick attribute, or still use it if you’re OK with its limitations.