This evening was Ask the Experts time at Microsoft’s BUILD conference in Anaheim, California, so I took the opportunity to ask the Internet Explorer (IE) team why the Metro-style IE does not support plugins such as Adobe Flash and even Microsoft’s own Silverlight.
I find it puzzling since the desktop IE in Windows 8 does support plugins, and when a page is open in Metro-style IE there is an option to open it in desktop Windows, in which case all the ActiveX controls start working.
The reason I was given is that Microsoft cannot control or predict the user experience if these plugins are running. For example, a Silverlight applet might have a user interface designed for mouse and keyboard. Microsoft has built in touch gestures that work for HTML in IE but cannot do so for plugins.
Once a user takes the decision to open in desktop Windows, these considerations change since desktop Windows is a mouse and keyboard environment.
I expect performance was also a consideration.
I was also told that Apple has made the no-plugins option viable by taking the same line in the iPad. Sites have been forced to offer iPad-friendly versions of their sites, which will also work in Windows 8 Metro.