Opera 10 for Windows changelog

Release notes

Release date: September 01, 2009

Opera 10 is a recommended upgrade offering new and improved features, plus security and stability enhancements. A separate changelog listing changes since Opera 10 beta 3 is available.

New features

Auto update

Opera now includes the ability to update itself automatically when new releases become available. By default, Opera will notify the user about available updates. Users can specify that snapshot build releases of Opera should be downloaded by enabling "Download All Snapshots" in opera:config. Users can also choose not to check for updates or to automatically install updates by going to Tools > Preferences > Advanced > Security and changing the "Opera update level" (select box) to the: "Automatically install updates" setting.

Crashlogging tool

An integrated user interface for built-in crash reporting has been added to Opera. This feature automatically appears when Opera has suffered a crash and enables a user to easily report the event directly back to Opera.

Inline spell checker

Spelling errors are now indicated as you type via a dotted red underline in all places where you can input text: form fields, Opera Mail compose windows, Notes, Chat, etc. Only single-line text fields do not check spelling automatically. The spelling checker can be enabled/disabled from the context menu (right-click a text field to open this menu). The context menu also includes spelling suggestions, the ability to change dictionary languages, and the ability to select additional dictionaries for automatic download and installation. Opera uses the Hunspell dictionary format, and a US English dictionary is included by default.

Opera Presto 2.2 rendering engine

The Opera Presto rendering engine has been updated to version 2.2 further enhancing its reputation for stability and security. It is identified by the following User Agent ID string located at Help > About Opera > Browser identification:

Opera/9.80 (Windows NT 5.1; U; en) Presto/2.2.15 Version/10.00

Opera Turbo

This new Opera feature increases your internet bandwidth speed on slow connections using data and image compression technologies. Opera Turbo uses Opera proxy servers to compress the traffic before it reaches the Opera browser on the client computer; see this Opera reference.

Get started with Opera Turbo.

  1. Click the Opera Turbo icon located on the left side of the Status Bar to turn it on.
  2. Clicking it again will turn it off.

Configuring Opera Turbo can easily be done to suit your browsing needs.

  1. Click the dropdown arrow located to the right of the Opera Turbo icon in the the Status Bar.
  2. In the menu, select "Configure Opera Turbo" to open the Opera Turbo Settings dialog box.
  3. The following choices can now be made:
    • Automatic (radio button): Turbo will enable only if it detects a slow network
    • On (radio button): Optimize pages with Turbo so they load faster on slow networks
    • Off (radio button): Load pages normally
    • Notify me about network speed (checkbox): network speed indicator becomes visible within the Opera Turbo icon on the Status Bar

Pretty-printing of unstyled XML

Opera 10 incorporates "pretty-print XML", which is now the default styling for unstyled XML and uses the unstyledxml.css style sheet in the Styles sub-directory of the Opera installation directory.

Skin elements

New skin elements crafted by our acclaimed Web designer Jon Hicks have been applied to the Opera 10 user interface. Among them are:

Visual tabs

The Opera 10 Tab Bar can be used to show all open tabs as thumbnails.

  1. If the Tab Bar is not open by default, open it in the Opera 10 user interface:
    • In the main Opera Tool Bar, navigate to View > Toolbars > Tab Bar.
    • Click the Tab Bar check box. This opens the Tab Bar in the Opera user interface.
  2. In the Tab Bar, middle-click or double-click the drag bar [ ... ] to fully expand or collapse all open tabs into thumbnails, or
  3. Grab the lower border of the Tab Bar or grab the drag bar and:
    • move it down to expand all open tabs into thumbnails to a size of your choice
    • move it up to collapse all open thumbnails back into tabs
  4. Functional note: The Tab Bar select box is set to "No wrapping" by default (right-click the Tab Bar, in the context menu click "Appearance", "Wrapping" is set to the "No Wrapping" selection). Changing this selection to "Wrap to multiple lines" turns off Visual tabs.

You can also turn off Visual tab thumbnails if you prefer the traditional Opera tab environment.

  1. Right-click the Tab Bar.
  2. In the menu, point to "Customize".
  3. In the submenu uncheck the "Enable Thumbnails in Tabs" check box.

The Tab Bar can be moved from its default top position by using the new Tab Bar context menu option "Tab bar placement". Placing the Tab Bar on the left or right side of the Opera 10 user interface increases your vertical screen real estate.

  1. Right-click the Tab Bar.
  2. In the menu, point to "Tab bar placement".
  3. In the submenu select any one of the following Tab Bar positions.
    • Top (radio button): default - places the Tab Bar at the top of the Opera 10 user interface
    • Bottom (radio button): places the Tab Bar at the bottom of the Opera 10 user interface
    • Left (radio button): places the Tab Bar at the left side of the Opera 10 user interface
    • Right (radio button): places the Tab Bar at the right side of the Opera 10 user interface

Improved features

Acid3 test

Opera 10 scores 100/100, pixel perfect on the Acid3 compliance test; see our Opera reference.

Opera Dragonfly

Additions to Opera Dragonfly developer tools include HTTP header inspection, DOM editing, and automatic selection of the current tab; see this Opera reference.

Opera Mail: Delete After X Days — POP-only

Delete after X days automatically removes messages from POP servers after the specified number of days, which is particularly useful for users who have limited server space. This option can be enabled for POP accounts on the Incoming tab of the account settings dialog by checking "Remove from server after #days" (7 days by default). It is also possible to specify that only read messages and/or only fully downloaded messages should be removed. Warning: Disabling the latter option is dangerous for those that use low-bandwidth mode, as messages that are not completely downloaded will be removed from the server, making it impossible to retrieve the complete message.

Opera Mail: Rich Text Message Composition — HTML authoring

Opera Mail can now send rich text messages including inline images, styled text, links, and/or custom HTML.

Regular expression engine

Opera 10 has an improved and faster regular expression engine that uses a stack-based bytecode instruction set. This type of instruction set is based around a stack of values, where most instructions "pop" input operands from the value stack, process them, and "push" the result back onto the value stack. Some instructions simply push values onto the value stack, and others rearrange the values on the stack. This results in compact bytecode programs with code that is easily generated. It is a typical backtracking regular expression engine, but does some tricks to avoid redundant backtracking. These usually avoid the severe performance issues a backtracking regular expression engine can have on specific regular expressions.

Speed Dial configuration options

You can now easily configure how many speed dials will fit comfortably on your Opera desktop. Click "Configure Speed Dial" in the lower-right corner of the Speed Dial page to open the configuration dialog box. Three tools are available:

Web specifications support

CSS (Cascading Style Sheets)
SVG (Scalable Vector Graphics)
Web fonts

See this Opera reference and demonstration.

Changes since Opera 9.64

User Interface


Mail, News, Chat


Display and scripting









Opera Help

Need help? Hit F1 anytime while using Opera to access our online help files, or go here.