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

Improved features

• Acid3 test - Opera 10 scores 100/100, pixel perfect on the Acid3 compliance test.
• 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: 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.
• 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.
• Web specifications support

CSS (Cascading Style Sheets)

• Support for the CSS3 color:transparent value has been improved.
• Full RGBA and HSLA opacity support is now included for an easier way to make Web page features transparent. This is accomplished by the addition of a fourth argument to HSL and RGB, namely alpha transparency and results in RGBA and HSLA values. See this Opera reference.
• Support has been added for the CSS Selectors API. This feature makes the selection of DOM elements a lot simpler. It includes partial support for namespace resolver features which allow you to work with mixed namespace documents and select elements based on their namespace; see this Opera reference.
• CSS files must now be served with the correct MIME type ("text/css") in Strict mode, or they will be ignored.

HTML 5

• HTML 5 algorithms have been implemented for detecting charsets in HTML.
• HTML 5 end-tag and start-tag parsing, whitespace parsing, and DOCTYPE parsing have been added.
• HTML 5 <canvas> elements can now export images to the JPEG format.
• HTML 5 <canvas> transforms are applied when building a path, not when painting it.

SVG (Scalable Vector Graphics)

• FPS (Frames Per Second) support: Opera enables you to manipulate the speed (frames per second) of your SVG animations using JavaScript by supporting the SVGElement.currentFps and SVGElement.targetFps properties. These properties respectively read and control SVG frames per second; see this Opera reference.
• SVG fonts in HTML support: Use SVG font files to style your text using CSS (in both HTML and SVG files); see this Opera reference.

Web fonts

• font specification (@font-face CSS at-rules) with the font-family descriptor
• src descriptor with local and remote
• TrueType (TTF)
• OpenType (OTF)
• Scalable Vector Graphics (SVG) font support

Changes since Opera 9.64

User Interface

Added

• Ability to reset toolbar customization
• Resizeable search field
• Opera Turbo warning icon
• Warning and advice about why dictionaries.xml file sometimes is missing from Auto update
• A "Synchronize Opera" button in the Speed Dial page
• Tab icons (inverted) for panels viewed as tabs
• An Open Folder menu item to the file browse control
• Multiple-server support for Auto Update
• A left-click context menu to the Opera Turbo button
• A context menu option to reload images in high quality
• Password Manager with context-menu support
• Translations into 39 languages including English
• Belorussian
• British English
• Bulgarian
• Chinese Simplified
• Chinese Traditional
• Croatian
• Czech
• Danish
• Dutch
• Estonian
• Finnish
• French
• Canadian French
• Frisian
• German
• Greek
• Hindi
• Hungarian
• Indonesian
• Italian
• Japanese
• Korean
• Lithuanian
• Macedonian
• Norwegian Bokmål
• Norwegian Nynorsk
• Polish
• Portugese
• Brazilian Portugese
• Romanian
• Russian
• Serbian
• Slovak
• Spanish
• Latino Spanish
• Swedish
• Turkish
• Ukrainian

Improved

• "Remove From Toolbar" and other toolbar customization options moved into a submenu
• Allowed Speed Dial to have a custom favicon
• Implemented a progressive disclosure control on "Report a site problem" dialog box
• All submenus are now given icons from the skin
• Windowless Silverlight no longer disappears when using context menu
• Windows Media Player plug-in is now recognized on Win 9x operating systems
• Opera now automatically adds itself to exceptions in Windows firewall
• Pressing Enter to select an item in a dropdown box no longer submits a form
• Enabled tab thumbnails check box by default in Customize dialog box
• Notification now shown when Opera Turbo servers are busy
• Improvements to hover state on tabs (better contrast) and tabs on the side
• Panels viewed as Tabs now have their own favicon and thumbnail image
• Images appended after page load will now display until "screen refresh"
• Updated appearance of standard-skin dialog boxes
• Images to be used as desktop background are only saved in the user's profile pictures folder

Fixed

• Text overlaps in Visual tabs
• Aborting the printing of a Web page
• Windows Media Player not painting when going back/forward and occasionally on first load
• Error dialog during Auto update when selecting the current limited user in the Run As dialog box using a limited account on WinXP
• Opera Turbo "Automatic" mode not being reflected in the status field
• Translated strings in Romanian not fitting the error-report and Appearance dialog boxes
• Tiled background in Speed Dial not being remembered
• Internet-to-Intranet override polishing
• Setting Opera Turbo through the Details dialog box
• Opera continuously opening tabs if choosing "Opera Internet Browser" and "Remember choice" in the BitTorrent Client Selection dialog
• BT download dialog box now inherits most of the functionality from the download dialog, including the Save functionality
• Creating a search when right clicking on a search text field
• Yahoo! mediaplayer in learnenglish.de
• Spatial navigation on the Yahoo! frontpage
• Saving a picture that has not been fully downloaded
• Uninstalling a dictionary
• Session not being saved when closing Opera
• Downloading a new .torrent file with Opera Turbo enabled
• The Wikipedia Cortado Java Theora player working in Opera 10
• Posting/loading of links on a wall at Facebook
• SVG background images disappearing on hover
• Switching to English when auto updating
• Problem with the nytimes.com page while closing Opera
• System-wide settings not being read
• Display of Visual tab thumbnails when page uses bitmap fonts
• Wrong name being listed for Azureus in the BitTorrent Client Selection dialog box

Renamed

• "Transfers" to "Downloads"
• "Wand" to "Password Manager" (Tools > Advanced > Password Manager)

Mail, News, Chat

Added

• Delete after X number of days facility
• Horizontal scrollbars in e-mails
• A recovery mechanism for corrupt mail databases
• Additional online feed readers to the feed preview page
• Keyboard shortcuts for Go to Thread: D, Watch Thread: Ctrl-D, and Ignore Thread: Ctrl-Shift-D
• A thread button to the message list toolbar
• A dialog to warn about the mail database consistency check
• Several icons to the Compose menu

Improved

• Adding links to HTML e-mails
• Sent e-mails show when using threading in the e-mail client
• Removed the encoding mismatch dialog
• Threaded messages sorted by date now sorted by the last arrived message instead of the first
• Right-to-left (RTL) text improvements:
• autodetection of RTL
• sending of RTL HTML messages
• replying to RTL messages should reply in RTL ++
• HTML e-mail composition
• Clicking on a new message notification when:
• trying to find a window where the message is visible
• trying to open unread if it is visible there
• trying to open the account view if it is not visible there

Fixed

• Mail compose issues
• Double-clicking a note to insert into mail when replying
• 8 bit not being the default content-transfer encoding
• Opera Mail welcome message encoding and other strings
• HTML keyboard shortcuts working in plain text mode
• Chat connection status for multiple accounts
• Plain text e-mail composing
• Printing mail which resulted in an empty page
• Ability to paste into inline find in mail view
• Decoding error when writing an HTML mail with a non-ASCII character
• Text not fitting in several dialog boxes when switching to the Romanian language
• Signature not changing when changing an account

Display and scripting

Added

• W3C Selectors API support
• Basic Web font support:
• font specification (@font-face CSS rule) with the font-family descriptor that controls font choices
• src descriptor with local and remote
• Truetype (ttf) and Scalable Vector Graphics (svg) font support
• Support for SVGElement.currentFps and SVGElement.targetFps properties to read and control SVG frames per second
• An "Open Folder" menu item to the file browse control

Improved

• Full RGBA support
• Ojects returned by getClientRects() and getBoundingClientRect() renamed to ClientRectList and ClientRect instead of TextRectangle and TextRectangleList
• XMLHttpRequests now trigger start-loading/end-loading events
• Removed proprietary window.setDocument method
• Load event for scripts now sent after the script execution rather than before
• Load event now sent to frame/iframe/object elements before being sent to the document
• Highlights no longer added when HTMLElement.focus() is called unless keyboard navigation is already activated
• Web fonts loaded in memory and the font name being retrieved
• FormatBlock now correctly affects ancestors of the contentEditable element
• browser.js can now be disabled when doing Auto update
• DOMContentLoaded now fires when traversing history
• Support for getting localized strings from JavaScript
• Max values now set for the automatic memory cache

Fixed

• getElementsByClassName which now works with multiple classes in className
• Hardcoded strings in XML files
• Scope when defining getter for the HTMLElement document prototype
• Recursive regular expression causing stack exhaustion
• An issue with TinyMCE and Opera Dragonfly

Network

Added

• A link on the error page for cross-network communication

Improved

• Network access for widgets is now opt-in
• All existing widgets must be updated to have network access
• All widgets on widgets.opera.com given Internet access
• Network access specified using the network attribute of the widget element:
• Widgets using <widget network="private"> will have Intranet access only
• Widgets using <widget network="private public"> will have Intranet and Internet access

Security

Added

• Support for TLS 1.2
• Full set of padlock icons for security dialog box

Improved

• Anti-spoof checking and prevention of spoofing of services

Changed

• Phased out root certificates using MD2 signatures; see our advisory
• Removed support for SSL v2 and weak ciphers

Fixed

• Issue where sites using revoked intermediate certificates might be shown as secure; see our advisory
• Issue where the collapsed address bar didn't show the current domain; see our advisory
• Some IDNA characters not correctly displaying in the address bar; see our advisory
• Issue where Opera accepts nulls and invalid wildcards in certificates; see our advisory
• Recognizing EV certificates issued directly from the Root
• Importing certificates

Miscellaneous

Added

• Support for the altGlyph element in SVGs
• Support for 32-bit alpha in BMP and RLE-encoded BMP images
• A placeholder in Opera Turbo for plug-ins that are not loaded yet
• Functionality for switching Opera Turbo mode off for separate image elements

Improved

• Image downloading
• http://www.w3.org/TR/REC-html40 namespace no longer recognized or supported as an alias of http://www.w3.org/1999/xhtml.
• Files generated by the Opera installer use same naming scheme across different platforms
• Removed support for UTF-32 encoding
• User JS files now executed in alphabetical order rather than file system order
• Now possible to add Opera Turbo configuration files per language

Fixed

• Gmail problems
• A problem with Facebook chat
• Font fallback problems, particularly for those using Russian as their default language in Windows
• Several memory leaks
• Several stability issues
• Loading an automatically saved session
• Various dialogs with third-party mouse plug-ins installed
• High memory use related to the disk cache on large torrents

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