Programming - - By Andrew Tetlaw

Really? IE9 100% Compatible with HTML5?

Visiting the IE Test Center site you may be forgiven for thinking that IE9 has scored 100% compatibility with HTML5. They have constructed a test results table that compares the current IE9 platform preview with current versions of all the other major browsers. IE9 scores 100% on all of their tests, even the one labeled “HTML5.”

However, on closer inspection, it’s clear they’ve only added tests for a very limited subset of functionality under the HTML5 label:

  • HTML5 JavaScript text selection API
  • Embedding SVG in HTML
  • The JavaScript getElementsByClassName function

HTML table of test results showing IE9 scoring 100% for all tests

So, it’s not really a HTML5 compatibility test. As Dave here at SitePoint HQ succinctly put it:

We’ve created this IE9 conformance test suite and we’ve concluded that none of these other browsers are IE9.

Visiting The HTML5 Test website paints a completely different picture. From the testing I did, the best browser was Google Chrome 5, which scored 142/160, Safari 4 achieved 120, Opera 10.5 received 38102, and Firefox 3.6 scored 101. The worst scoring browsers were IE8 and the second IE9 platform preview; both scored 19/160.

To demonstrate that anyone can play the test results game, the Internet Explorer 9 HTML5 Canvas Campaign site has published a set of HTML5 test results that demonstrate IE9 consistently scoring 0%.

Personally, I’m excited about IE9. Who’d have thought Microsoft would have ever natively supported SVG? It’s also way too early to tell how well IE9 will support technology like HTML5 and CSS3; we only have an early platform preview so far. I have high hopes, though!

In the meantime, blatantly misleading test results like this help no one and only create confusion and mistrust.

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