Appendix 1: Internet Explorer 6 to Internet Explorer 9 Browser Changes

  Design Changes from Internet Explorer 6 to Internet Explorer 7 Design Changes from Internet Explorer 7 to Internet Explorer 8 Design Changes from Internet Explorer 8 to Internet Explorer 9

Internet Explorer Versioning

  • When a long user agent (UA) string encounters a server that accepts shorter UA string only, the user will be presented with an error page.

  • Internet Explorer 8 Compatibility View mode, turned on by default for intranet sites in Internet Explorer 8, actually sends an Internet Explorer 7 user agent string; to differentiate between Internet Explorer 7 and Compatibility View, look for the new Trident token.

  • Check for code that incorrectly creates a special case for Internet Explorer, Internet Explorer 8, or Internet Explorer 9 by using user agent (UA) string sniffing, version vectors, or conditional comments.

  • Internet Explorer 9 sends a short UA string by default, without pre- and post-platform registry value tokens.

  • Compatibility View mode, turned on by default for intranet sites in Internet Explorer 8, actually sends an Internet Explorer 7 user agent string; to differentiate between Internet Explorer 7 and Compatibility View in Internet Explorer 8, look for the Trident 5.0 token.

Note

  • Check for code that incorrectly special cases around Internet Explorer 6, Internet Explorer 7, or Internet Explorer 8 by using user-agent string sniffing, versions vectors, or conditional comments.

  • Quirks mode exception: As a rule of thumb, no standards compliance changes are needed for webpages that specify the Quirks mode DOCTYPE (by setting “standards-compliance” DOCTYPE switch to “off”).

  • Design Changes from Internet Explorer 6 to Internet Explorer 7 Design Changes from Internet Explorer 7 to Internet Explorer 8 Design Changes from Internet Explorer 8 to Internet Explorer 9

    Standards Compliance Updates

    Applies to Internet Explorer 7 Standards or “Strict” mode and above:

    Applies to Internet Explorer 8 Standards mode and above:

    Applies to Internet Explorer 9 Standards mode and above:

    For more information about other changes, see Web Applications and Standards/Interop Improvements on these posts.

    Applies to all document modes in Internet Explorer 9:

    Note

  • For sites and applications where accessibility is a concern, be sure to update ARIA syntax across all Internet Explorer rendering modes.

  • Check the complete list of CSS updates from Internet Explorer 6 to Internet Explorer 8.

  • Internet Explorer 9 contains some assistive technology improvements, but is not fully functional with some assistive technologies. See the list of issues in the Internet Explorer 9 release notes.

  •   Design Changes from Internet Explorer 6 to Internet Explorer 7 Design Changes from Internet Explorer 7 to Internet Explorer 8 Design Changes from Internet Explorer 8 to Internet Explorer 9

    Security Improvements

    • Apply regardless of document mode.

    • Security features can be turned off using Group Policy.

    • Style sheets are ignored unless they are delivered with the text/css MIME type.

    • HTML documents delivered with a text/plain MIME type render or download as plain text only and are not MIME-sniffed to another type.

    • SCRIPT and STYLESHEET elements reject responses with incorrect MIME types if the server sends the response header X-Content-Type-Options: nosniff.

    See other security updates in the Security sections of these blog posts:

    Architectural Changes

    • Apply regardless of document or compatibility mode.

    • Protected Mode Update: Intranet now runs in medium (instead of low) integrity level by default.

    • Loosely Coupled IE may block add-ons (that is, ActiveX controls and COM objects) that: 1) Use windows hierarchy techniques to locate UI frame and tab windows (which now run in separate processes at different integrity levels), 2) Create a subclass of the UI frame (now at medium integrity level) from a low-integrity tab process, 3) Use unsupported messaging techniques between UI frame and tabs.