Microsoft responds to claims of poor Internet Explorer 9/HTML5 compliance

Microsoft responds to claims of poor Internet Explorer 9/HTML5 compliance

Over the weekend we brought you the story of a developer and his attempt to get his site working on Internet Explorer 9. He had massive HTML5 compliance issues that created a situation so wonky that he called it a “hilarity.”

Microsoft, after reading both our post and his took the time to craft a response that addresses at least most of the concerns that the developer had.

It would be unfair to not cover their response, and so as best as we can, what follows is a breakdown of what Microsoft has to say on the subject of IE9/HTML5 compatibility and performance. There were three main points that were raised, problems with: globalCompositeOperation, Canvas Resizing, and Limited Shadow Offset. We will take the Redmond response one at a time.


As you noted, globalCompositeOperation is not supported in Platform Preview 7. Or, better, we support only the source-over state. We do care about supporting this property, but we also care about it being interoperable across all browsers.

At the time we announced and shipped support for the Canvas, the other browsers were supporting the globalCompositeOperation, but they didn’t have the same rendering behaviors – making developer life very complex.

[…] Given that evident interoperability challenge, we decided it was critical to have first that conversations with the HTML Working Group – before shipping something unreliable for end-users. Since then, we believe we made good progress – you should expect to hear more from us soon.

Or, in normal speech, Microsoft held off shipping code until they were sure exactly how it should perform. That we should “expect more soon” implies that they have gotten the standard straight and will ship a fix in a later version. Recall that IE9 is still beta.

Canvas Resizing

According to Microsoft this is an old bug that has already been fixed, but not shipped. In other words, it is just a matter of time until this problem disappears for good. Annoying that it happened, but not deadly as it has been handled.

Limited Shadow Offset

This is perhaps the only problem of the three that stumped our intrepid MSFT blogger. He sadly stated that he could “repro [the error] on my machine.” He went on to test the function in question on the four main browsers, and came up with the following collection, in which he claims that Firefox is doing the best job:

In other words, one of the developer’s problems has already been fixed, another was Microsoft waiting for the spec to be settled, and the last appears to be a smaller issue. All in all, Internet Explorer 9, if demonstrated by nothing else than the zeal of its team, is dedicated to correct and full HTML5 compliance. Here’s to hoping that IE9 goes RTM quickly.

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