Platform Preview 4 (PP4) release ) only works on Windows 8. This is not an update to the Platform Preview of IE 10 on Windows 7 but this release is for IE 10 on the Developer Preview pre-beta build of Windows 8 only. IE 10 PP4 is said to add even more support for HTML5 technologies, enabling richer Web applications. Some of the additions:
- Addition of the CSS user-select property to control how end-users select elements in a Web page or application.
- Support for HTML5 video text captioning, including time-code, placement, and captioning file formats.
- Support for CORS (cross origin resource sharing), which allows developers to use XMLHttpRequest to request, share and move data across applications on different domains.