Originally posted on the IE Blog.
We have updated Internet Explorer 10 in Windows 8 and Windows RT to enable Flash content to run by default. On Windows 8, all Flash content continues to be enabled for IE on the desktop.
As we have seen through testing over the past several months, the vast majority of sites with Flash content are now compatible with the Windows experience for touch, performance, and battery life. With this update, the curated Compatibility View (CV) list blocks Flash content in the small number of sites that are still incompatible with the Windows experience for touch or that depend on other plug-ins.
We believe having more sites “just work” in IE10 improves the experience for consumers, businesses, and developers. As a practical matter, the primary device you walk around with should give you access to all the Web content on the sites you rely on. Otherwise, the device is just a companion to a PC. Because some popular Web sites require Adobe Flash and do not offer HTML5 alternatives, Adobe and Microsoft continue to work together closely to deliver a Flash Player optimized for the Windows experience.
This updates the immersive IE experience on Windows 8, and both the immersive and desktop IE experiences on Windows RT. The update will be made available to customers with Windows Update. The curated CV list applies to IE on the desktop for Windows RT since the most common reason to block Flash is that the site relies on other plug-ins that are not available on Windows RT.
More compatible Web experiences
Our approach to Flash in Windows is practical for Windows customers and developers. For Windows 8, we worked with Adobe to include a version of Flash that is optimized for touch, performance, security, reliability, and battery life. Adobe made substantial changes to the Flash player to align with the Windows 8 experience goals. We shipped this optimized Flash component as part of Windows 8, and we service it through Windows Update. IE10 with Flash on Windows 8 enables people to see more of the Web working with high quality, especially compared with the experience in other touch-first or tablet browsers and devices.
When we released Windows 8 and Windows RT we used the IE Compatibility View (CV) list to enable sites to run Flash content compatible with the Windows 8 experience, including touch responsiveness, performance, and battery life. In Windows 8, IE on the desktop runs all Flash content, like it does on Windows 7.
Looking at our engineering experience with Flash and Windows 8 and RT, as developers improve their Flash content, the vast majority of sites with Flash content that we have tested are now compatible with the Windows experience goals. Of the thousands of domains tested for Flash compatibility to date, we have found fewer than 4% are still incompatible, in the most part because the core site experience requires other ActiveX controls in addition to Flash. With Windows 8 in the hands of customers and developers, we listened to feedback around the experience of Web sites with Flash.
Developing compatible Flash content
For developers building sites with Flash content, this document posted on MSDN goes into more technical detail about the criteria used to place sites on the Flash CV block list, as well as steps that developers can take to test their content in immersive IE and submit their sites to be removed from the block list. The documentation also includes a best practices guide to help developers, designers, and content publishers create experiences with Flash that play well in IE for touch, responsiveness, and battery life. These best practices complement existing recommendations and tools like modern.IE for authoring touch-friendly HTML5 sites. Also, starting tomorrow, modern.IE enables testing whether or not your site is on the curated Flash CV block list.
For the development community, platform continuity and technology choice are important. Flash in IE10 on Windows 8 and Windows RT provides a bridge for existing sites to transition to HTML5 technologies where it makes sense and at a pace that is right for the experiences they want to deliver to their customers. With today’s update to Windows 8 and Windows RT, consumers can experience more of the Web by default.
— Rob Mauceri, Group Program Manager, Internet Explorer