Its Ruby character extension to HTML is also accepted as a module in W3C XHTML 1.1, though it is not found in all versions of W3C HTML.
Microsoft submitted several other features of IE for consideration by the W3C for standardization.
This has resulted in a number of web pages that appear broken in standards-compliant web browsers and has introduced the need for a "quirks mode" to allow for rendering improper elements meant for Internet Explorer in these other browsers.
Internet Explorer has introduced a number of extensions to the DOM that have been adopted by other browsers.
Multiple files exist which index different content—visited content, web feeds, visited URLs, cookies, etc.
Prior to IE7, clearing the cache used to clear the index but the files themselves were not reliably removed, posing a potential security and privacy risk.
Pop-up blocking and tabbed browsing were added respectively in Internet Explorer 6 and Internet Explorer 7.
Internet Explorer also supports Integrated Windows Authentication. Previous versions had a similar architecture, except that both tabs and the UI were within the same process.
Internet Explorer was criticised by Tim Berners-Lee for its limited support for SVG, which is promoted by W3C.
Internet Explorer has introduced an array of proprietary extensions to many of the standards, including HTML, CSS, and the DOM.
According to Microsoft, development of new features for Internet Explorer has ceased.
However, it will continue to be maintained as part of the support policy for the versions of Windows with which it is included.
Internet Explorer uses DOCTYPE sniffing to choose between standards mode and a "quirks mode" in which it deliberately mimicks nonstandard behaviours of old versions of MSIE for HTML and CSS rendering on screen (Internet Explorer always uses standards mode for printing).