On January 5, 2009, a tool was provided by Microsoft to block the automatic install of Internet Explorer 8 via Windows Update.^[4]

According to Microsoft, security, ease of use, and improvements in RSS, Cascading Style Sheets, and Ajax support are its priorities for Internet Explorer 8.^[5][6]

History

IE8 has been in development since at least March 2006.^[7] In February 2008, Microsoft sent out private invitations for IE8 Beta 1,^[8] and on March 5, 2008, released Beta 1 to the general public,^[2] although with a focus on web developers.^[9]

The release launched with a Windows Internet Explorer 8 Readiness Toolkit website promoting IE8 white papers, related software tools, and new features in addition to download links to the Beta.^[2][10] The Microsoft Developer Network (MSDN) added new sections detailing new IE8 technology.^[2][10][11] Major press focused on a controversy about Version Targeting, and two new features then called WebSlice and Activities. The readiness toolkit was promoted as something "developers can exploit to make Internet Explorer 8 'light up'." ^[2]

On August 27, 2008, Microsoft made IE8 Beta 2 generally available.^[1] PC World noted various Beta 2 features such as InPrivate mode, tab isolation and colour coding, and improved standards and compatibility compared to Internet Explorer 7.^[12] Two name changes included Activities to Accelerators, and the IE7 Phishing filter renamed Safety Filter in the first Beta to SmartScreen, both accompanied by incremental technical changes as well.^[12] By August 2008 the new feature called InPrivate had taken the spotlight.^[12]

Features

Overview

The first beta release of IE8, which was demonstrated at the MIX08 conference, contained many new features, including WebSlices and Activities.^[13] In the second beta release, Activities were renamed to Accelerators.^[14]

Added features

Some of the features and changes for the Beta 2 compared to Beta 1.^[12]

• InPrivate^[12]
• Delete Browsing History
• Search Suggestions
• User Preference Protection
• Caret Browsing
• Accelerators (previously known as Activities)
• Web Slices (previously known as WebSlices)^[12]
• Suggested Sites
• Tab Color Grouping^[12]
• Automatic Crash Recovery
• SmartScreen Filter (Known as Safety Filter in Beta 1)
• Tab isolation (tabs spread over separate operating system processes)

Removed features

• Inline AutoComplete^[15]
• The option to delete files and settings stored by addons or ActiveX controls.
• CSS Expressions are no longer supported in Internet Explorer 8 Standards mode^[16]

Suggested Sites

This feature is described by Microsoft as a tool to suggest websites, which is done by the browser sending information to Microsoft which keeps the information and IP Address for a short time.^[17] Suggested Sites is off by default and the user has to turn it on manually when desired.

InPrivate

A new security mode called InPrivate debuted with Beta 2, which consists of three main features: InPrivate Browsing, InPrivate Blocking, and InPrivate Subscription.^[12] Like similar privacy protection modes in Safari and Google Chrome, InPrivate Browsing has been described as a "porn mode" in various news outlets.^{[19][20][21][22][23][24][25][26]} Informationweek mentioned it as a "'Stealth' Privacy Mode".^[27]

Gregg Keizer of Computerworld says Private Blocking "notifies users of third-party content that can track browsing history", and that InPrivate Subscription allows "subscribing to lists of sites to block".^[27] When enabled, IE8 will not save browsing and searching history, cookies, form data and passwords; it also will automatically clear the browser cache.^[27]

Accelerators

Accelerators are a form of selection-based search which allow a user to invoke an online service from any other page using only the mouse.^[28] Actions such as selecting the text or other objects will give users access to the usable Accelerator services (such as blogging with the selected text, or viewing a map of a selected geographical location), which can then be invoked with the selected object. According to Microsoft, Accelerators eliminate the need to copy and paste content between web pages.^[13] IE8 specifies an XML-based encoding which allows a web application or web service to be invoked as an Accelerator service. How the service will be invoked and for what categories of content it will show up is specified in the XML file.^[29] Similarities have been drawn between Accelerators and the controversial Smart tags, feature experimented with in the IE 6 Beta but withdrawn after criticism (though later included in MS Office).^[9]

Web Slices

Web Slices are snippets of the entire page that a user can subscribe to.^[28] Web Slices will be kept updated by the browser automatically, and can be viewed directly from the Favorites bar, complete with graphics and visuals. Developers can mark parts of the pages as Web Slices, using the hAtom and hSlice microformat. Web Slices have been compared to Active Desktop, introduced in Internet Explorer 4 in 1997.^[30]

Microsoft donated the specification to the public domain under the Creative Commons Public Domain Dedication. It is also covered by the Microsoft Open Specification Promise.^[31]

Autocomplete changes

The address bar features domain highlighting for added security so that the top-level domain is shown in black whereas the other parts of the URL are grayed out. Domain highlighting cannot be turned off by users or web sites. Other features of the address bar include support for pasting multi-line URLs and an improved model for inserting the selection caret, and selecting words, or entire URLs in the Address bar. The inline autocomplete feature has been dropped from Internet Explorer 8.^[15]

SmartScreen Filter

SmartScreen Filter is an extension of Internet Explorer 7's phishing filter. If a user visits a site which has been labeled as an impostor or harmful, then Internet Explorer 8 will show a screen prompting that the site is reported harmful and shouldn't be visited. From there, the user can either visit his or her homepage, visit the previous site, or continue to the unsafe page.^[32] This feature can be disabled using Group Policy.

Developer tools

For developers, IE8 includes tools that allow HTML, CSS and JavaScript debugging directly from the browser.^[29]

Favourites Bar

Other new features in IE8 include a redesigned Favorites Bar, which can now host content such as Web Slices, web feeds as well as documents, in addition to website links.

Automatic Crash Recovery

A crash recovery mechanism has been incorporated; if the browser crashes, web pages being viewed may be recovered, at the user's discretion, when the browser is restarted.^[28]

Zooming

Full-page zoom now reflows the text to remove the appearance of horizontal scrollbars on zooming.^[33]

Performance and stability

Internet Explorer 8 includes performance improvements across the HTML parser, CSS engine, mark-up tree manipulation as well as the JScript runtime and the associated garbage collector. Circular Memory leaks, which resulted earlier due to inconsistent handling of JScript objects and DOM objects, have been alleviated.^[29] For better security and stability, IE8 uses the Loosely Coupled Internet Explorer (LCIE) architecture and runs the browser frame and tabs in separate processes. Glitches and hangs don't bring down the entire browser. It also leads to higher performance and scalability. Permissions for ActiveX controls have been made more granular - instead of enabling or disabling them globally, they can now be allowed on a per-site basis.^[33]

Rendering engine

IE8 improves rendering of content authored to various web standards (like HTML, CSS and JavaScript) in standards mode.^[34] Such changes might cause it to break compatibility as its behaviour differs significantly from that of IE7.^[35] In order to maintain backwards compatibility, sites can opt-into IE7-like handling of content by inserting a special meta element into the web page, that triggers the "IE7 standards mode" in the browser, using:^[34]

<meta http-equiv="X-UA-Compatible" content="IE=7" />

While the behaviour of the browser is unchanged from Internet Explorer 7 in "IE7 Standards Mode", in standards mode (the default IE8 rendering mode), IE8 supports Data: URIs, HTML object fallback, the abbr tag, CSS generated content and the display: table CSS rule, in addition to fixing a lot of CSS and HTML parsing bugs.^[36] As a result, IE8 Beta 1 passes the Acid2 test in IE8 standards mode (now called "standards mode").^[37][36] Also, the proprietary hasLayout property will be eliminated when using IE8 in IE8 standards mode.^[38] Microsoft has stated that Internet Explorer 8 will improve only some of the standards being tested by Acid3.^[39]

Compliance with the CSS 2.1 specification was a stated goal in Internet Explorer 8 by Microsoft, even including an attempt to support some CSS3 features. IE8 Beta 1 also partially supports CSS 2.1 Paged media (including the @page CSS rule and the left, right and first page selectors). In addition, it also supports the DOM: Storage, Cross Document Messaging (XDM) and the Selectors APIs. IE8 also adds cross-domain communication via the XDomainRequest object, that exposes a programming model similar to XMLHttpRequest. IE8 features an enhanced and standardized DOM, that brings it in line with implementations in other browsers. Attributes and properties in DOM objects are now handled differently, and the behavior of the getAttribute, setAttribute and removeAttribute modifiers have been changed to match the behavior of other browsers.^[29] Internet Explorer 8 also supports the Accessible Rich Internet Applications(ARIA) specification for enhanced accessibility in Ajax-based rich Internet applications.^[33]

Compatibility mode

Internet Explorer 8 was promoted by Microsoft as having stricter adherence to W3C described web standards than Internet Explorer 7. As a result, as in every IE version before it, some percentage of web pages coded to the behaviour of the older versions would break in IE8. This would have been a repetition of the situation with IE7, which (while having fixed a lot of bugs from IE6) broke pages that used the IE6 bugs to work around its non-compliance. This was especially a problem for offline HTML documents, which may not be updatable (e.g. stored on a read-only medium, such as a CD-ROM or DVD-ROM).

To avoid this situation, Microsoft proposed Version Targeting whereby a page could be authored to a specific version of a browser using the X-UA-Compatible declaration either as a meta element or in the HTTP headers.^[48].

In order to maintain backwards compatibility, sites can opt-into IE7-like handling of content by inserting a specially created meta element into the web page, that triggers the "Compatibility mode" in the browser, using:^[40]

<meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7" />

A browser with a newer version than what the page has been coded for would emulate the behavior of the older version so that the assumptions the page made about the browser's behavior holds true.

Microsoft proposed that a page with a doctype that triggers standards mode (or almost standards mode) in IE7 would, by default, trigger IE7-like behavior, called "standards mode" (now called "strict mode") in IE8 and future versions of IE. The new features of IE8, along with the breaking changes, could be enabled by explicitly using the X-UA-Compatible declaration to trigger what Microsoft called the "IE8 standards mode" (now called "standards mode"). Microsoft's reasoning was that by making the choice to opt for standards compliance explicit, pages that do not want the behavior will not trigger the IE8 standards mode.^[48] IE8 standards mode could also be triggered by the HTML5 doctype. Doctypes that trigger quirks mode in IE7 will continue to do so in IE8.

The proposal was met with much controversy. Jeremy Keith, writing for A List Apart, felt that tying pages to browser versions would greatly hinder progressive development as championed by web standards.^[49] Håkon Wium Lie, Chief Technology Officer of Opera Software, authors of the Opera web browser, stated in an article for The Register that the move was an example of monopolistic behaviour due to Microsoft's dominating position in the web browser and operating system markets.^[50]

Peter Bright of Ars Technica claimed that the idea of using a meta tag to pick a specific rendering mode fundamentally misses the point of standards-based development, but positioned the issue as one of idealism versus pragmatism in web development, noting that not all of the Web is actively maintained, and that, "demanding that web developers update sites to ensure they continue to work properly in any future browser version is probably too much to ask."^[51]

On March 3, 2008, Dean Hachamovitch announced that Microsoft had changed their minds, opting instead to make the "IE8 standards mode" (now called "standards mode") the default in IE8 (i.e., pages with doctypes that trigger standards mode in IE7 as well as newer doctypes).^[40] Version targeting would still be present but now would be used to opt out of progressive development and use the IE7 standards mode (now called "strict mode"). While this move was praised by many of the same people who had criticized Microsoft's original choice, including Microsoft's competitors,^[52] the subsequent release of Internet Explorer 8 Beta 1 revealed that many web sites do not work in this new standards mode.

The result for IE 8 Beta 1 was that it could render three modes: "Quirks," "Strict," and "Standard." When there is an old DOCTYPE or when there is no DOCTYPE, IE renders it like IE5 would (quirks mode). When a special meta element or its corresponding HTTP header is included in a web page, IE8 will render that page like IE7 would (strict mode). In all other cases, IE8 renders pages with its own engine (standard mode). Users can switch between the three modes with a few clicks.^[16]

Market and critical response

Five weeks after the release of IE 8 Beta 2 in August 2008, Beta 1's market share had grown from 0.05% to 0.61%, according to Net Applications.^[49] A review of IE 8 Beta 2 by PC World summarized its thoughts on IE8 Beta 2 adoption:

"While it likely won't convince many Firefox users to jump ship, Internet Explorer 8 Beta 2 may be worth considering for people who have not yet solidified their browser loyalties."^[12]

IE 8 Beta 2 launches execution threads for each tab. It will use more memory if it is available than IE7 or Mozilla Firefox 3, which has led to some criticism.^[50]

Releases

The final product will be made after the Release Candidate.

Hardware requirements

IE8 RC1 requires at least:^[57]

• 233MHz processor or higher
• Super VGA (800 x 600) or higher-resolution monitor with 256 colors.
• Microsoft Mouse, Microsoft IntelliMouse, or compatible pointing device.
• RAM: 64MB for Windows XP/Server 2003 (32-bit) and 512MB for Windows Vista