error in W3C validation

Question

I am using Bootstrap 3.

When I add <meta http-equiv="X-UA-Compatible" content="IE=edge">, the site shows error in the W3C validator.

You could remove it and have something go wrong in IE, or leave it there and fail validation. I know what I'd do. — alex, Mar 20 '14 at 05:16

score 1 · Answer 1 · edited May 23 '17 at 11:53

From my answer to a similar question:

In (X)HTML5, you may only use http-equiv values that are

defined in the HTML5 spec, or

registered in the WHATWG wiki page "PragmaExtensions".

The value X-UA-Compatible is not defined in the spec, but it’s proposed in the wiki. "Proposed" means:

The following proposed extensions do not yet conform to all the registration requirements in the HTML spec and are therefore not yet allowed in valid documents.

So currently it’s not valid to use this value in (X)HTML5.

score 1 · Answer 2 · edited Oct 14 '14 at 15:53

1

You can do:

<!--[if IE]>
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<![endif]-->

edited Oct 14 '14 at 15:53

Marcin Nabiałek

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answered Oct 14 '14 at 15:30

stephen

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And then it won't trigger in IE10 or IE11. – Quentin Oct 14 '14 at 16:00

score 0 · Answer 3 · answered Mar 20 '14 at 06:30

0

The validator is extremely pedantic. It's best to just ignore this particular validation warning, given its significant pragmatic benefit and complete lack of downsides. It's not an error of any kind in any of the major browsers.

answered Mar 20 '14 at 06:30

cvrebert

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error in W3C validation

3 Answers3