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Today, Microsoft has released a new developer preview for IE11 on Windows 7, and it’s got a few new tools that web developers will find very interesting, particularly around monitoring performance and memory usage.
“There’s a lot of work that we’ve done around things like performance and standards support,” IE marketing director Roger Capriotti told VentureBeat in an interview this week
“From a performance perspective, we have the fastest JS engine. … The Chakra JS engine is around 15 percent faster than IE10 and 50 percent faster than Chrome.”
He also said IE11 for Windows 7 is the first browser that natively decodes JPEGs on the graphics card — meaning serious performance benefits for image-heavy sites — and the first to implement W3C resource prioritization spec, to load stuff the developer wants to load first.
Also, IE11 for Windows 7 meets a new set of standards met around WebGL, Flexbox, CSS border image support, and HTML5 drag-and-drop.
But what really gets us excited is the revamped set of F12 tools.
As Adarsh Nair, another IE marketing guy, said in the same chat, “It’s critical that sites have a super fast UI, and it’s even more critical for touch devices.”
So the new F12 tools show you where exactly are the page elements that are not performant, where the frame rate dips. You can see how memory is being used in real time; you can grab screenshot of the page during memory analysis to see where memory is varying. “You can quickly identify memory leaks,” said Nair.
There are also emulators for phones with specific sizes and resolutions. You can see the UI and how the code looks in practice. You can also emulate GPS for anywhere in the world.
While the tolls are focused on IE11, the code you create will be equally performant in speed and memory usage in Chrome and Firefox, Nair said.
Updates to Modern.ie will help non-Windows developers who don’t have a bunch of Microsoft hardware by recreating screenshots and emulating them for IE on a slew of different devices.
Check out some of these demos:
Capriotti demoed the LiteBrite game for us, showing off IE11′s performance in benchmark tests.
“All these experiences that we’ve launched, we’ve been trying to show consumers what the web can be, what they can experience in a browser,” he said.
“It doesn’t just have to be native apps.”
That’s long been the theory of web evangelists, but Microsoft, he continued, is taking experiments and demos and moving that performance and experience into real-world sites.
Nair then took us through a demo of the Everest summit-themed site with 3D models that use satellite data.
Summing up the mission statement of Microsoft’s recent work with IE, he said, “You can do incredible things on the web, on IE, on Windows, and that’s what you see here.”
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