Microsoft: No plug-ins allowed on Windows on ARM

As we Microsoft watchers continue to parse the 8,600-word post on Windows on ARM (WOA) that posted on February 10 on the "Building Windows 8" blog, more new questions are arising.

The latest: What are developers and customers who rely on browser plug-ins to do if they want ARM-based Windows 8 tablets and PCs?

Until yesterday, Microsoft's stance had been that it would offer two different versions of Internet Explorer 10 on Windows 8: A Metro-style version that wouldn't allow plug-ins; and a Desktop version that would allow plug-ins. Microsoft officials demonstrated at Build a Windows 8 ARM-based tablet that allowed a Flash plug-in. (Thanks to MVP Alan Burchill for finding that video, with the Flash demo starting at 2:20.)

Yesterday, Windows President Steven Sinofsky blogged that while there will be a Desktop experience on Windows on ARM, it will be very restricted. The Desktop on these devices will run only specially tailored "Office 15" versions of Word, Excel, PowerPoint and OneNote; the Windows File Explorer; Internet Explorer 10 and some unspecified other operating system tools/components. Sinofsky didn't note in his post that plug-ins were no longer supported in the Desktop version of IE10. ("The closest he came was saying "WOA does not support running, emulating, or porting existing x86/64 desktop apps.")

But in an interview with AllThingsD, Sinofsky is reported as having said "the version of Internet Explorer for Windows on ARM won’t support plugins such as Adobe Flash, noting the trend in the industry away from supporting Flash on mobile devices."

I'm thinking the Desktop IE version on the x86/x64-based Windows 8 tablets and PCs will continue to allow plug-ins. (I've asked Microsoft for verification, but no word back so far.)

It's no secret that the Windows and IE teams have been trying to steer developers away from Silverlight, Flash and plug-ins and toward HTML5/JavaScript. The Redmondians cite battery life, security and reliability as driving factors behind its decision to do so.

But it's not just ads that use these plug-ins. Many line-of-business apps and some consumer sites require legacy ActiveX controls. The way Microsoft planned to support these apps and sites was through the Desktop version of IE, which supported plug-ins.

Bottom line: Microsoft is touting Metro-style/WinRT as the way developers should go in creating apps for Windows 8. As of yesterday, it's officially no longer an option for third-party developers to recompile their existing Windows apps to run as Desktop apps on Windows on ARM. The only apps that will be allowed to run in the Desktop on Windows on ARM are a very few from Microsoft.

While the Metro-style apps will look, feel and be distributed/updated in the same way on Windows 8 on x86/x64 and ARM devices, the Desktops on those two classes of devices seemingly are going to be very different.