Updated functionality to the original XHR specification including things like file uploads, transfer progress information and the ability to send FormData. Previously known as XMLHttpRequest Level 2, these features now appear simply in the XMLHttpRequest spec. 4 - 6: Support unknown7 - 28: Partial support29 - 30: Partial support31 - 49: Partial support50 - 124: Supported125: Supported126 - 128: Su