Rocket Validator integrates the W3C Validator HTML checker into an automated web crawler.
HTML issues tagged as IE=edge.
The only value admitted for the attribute content in a <meta http-equiv="X-UA-Compatible"> is currently IE=edge. You’re probably seeing this issue because the page being validated includes the following meta tag:
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />
As the Google Chrome Frame plugin was discontinued on February 25, 2014, this is longer supported so you should change that meta tag to:
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
According to this article in Wikipedia:
Google Chrome Frame was a plug-in designed for Internet Explorer based on the open-source Chromium project, first announced on September 22, 2009. It went stable in September 2010, on the first birthday of the project. It was discontinued on February 25, 2014 and is no longer supported.
Still checking your large sites one page at a time?
Save time using our automated web checker. Let our crawler check your web pages on the W3C Validator.