Features of the Opera web browser: Difference between revisions

This article is about the features of the Opera web browser.

Opera was designed to run well even on low-end and small computers, and with a commitment to computer accessibility for users who may have visual or mobility impairments.

It is possible to control nearly every aspect of the browser using only the keyboard, and the default keyboard shortcuts can be modified to suit the user. Opera also supports the use of access keys to allow a computer user to immediately jump to a specific part of a web page via the keyboard. Opera was also one of the first browsers to support mouse gestures,^[1] allowing patterns of mouse movement to trigger browser actions, such as "back" or "refresh".

A "Fit to Window" feature that relies on technology similar to Opera Mini's Small Screen Rendering (SSR), allowing websites to fit within a smaller screen without the need for horizontal scrolling.

Opera offers true page zooming. Instead of just making the text bigger, this feature expands all page elements, including text, images, videos, and other content such as Macromedia Flash, Java and Scalable Vector Graphics to be increased or decreased in size (20% to 1000%) to help those with impaired vision. User stylesheets may also be used to do this and to enable high contrast coloured fonts. True page zooming prevents inconsistencies that occur when regular text enlargement forces the content to be bigger than its container.

Voice control, co-developed with IBM, allows control of the browser without the use of a keyboard or mouse. It can also read aloud pages and marked text. IBM has a browser based on Opera^[2].

The Opera browser provides for numerous tools and options to improve usability, simplify navigation, and aid the user in performing tasks relating to internet browsing.

Content blocker (also known as AdBlock).

Since: Opera 9, released June 20, 2006 - BitTorrent support

Opera allows the user to list, pause, resume or restart the downloading of files. It also keeps history of recently downloaded files and allows opening them from within the browser. Since Opera 9 introduced a built-in BitTorrent client, BitTorrent downloads can be handled within Opera just like regular HTTP/FTP downloads.

Opera can also be used with external download managers.

Since: Opera 6, released December 18, 2001

Hotclick refers to double-clicking any word in a page. Hotclick can be enabled by going to Opera’s Accessibility preferences. It was introduced in Opera version 6. It gives access to all search engines in Opera as defined by search.ini file, as well as giving access to the built-in translation, encyclopedia, and dictionary.

In addition to this, the Hotclick menu also gives access to the 'copy text', 'copy to note' (Opera 7 and later), and 'Send by email' functions. Using Hotclick is the fastest way to search for a word in Opera. Like all other menus, it can be customized in Opera 7 by using a custom menu ini file.

Opera has long had the option to load a page without graphics, or to use only images in the cache. This was very useful when dial up via modem was the overwhelming method for using a web browser. It remains useful today with overloaded servers. This is the only browser with such an easy method of turning graphics on or off.

Since: Opera 5.10, released April, 2001 - Gesture support

Users have the option of accessing common browsing functions with combinations of mouse movements.^[3] This option is similar to using keyboard shortcuts, as it saves time because users do not have to navigate to graphical buttons (thereby avoiding usability problems relating to Fitts' Law). Examples include:

• Back - Either pressing the left-mouse button while holding down the right button, or right-clicking anywhere and dragging the mouse towards the left.
• Forward - similar and opposite to the "back" gestures
• New Tab - holding down the right-click and dragging down.
• Scroll Through Tabs - scrolling with the mouse wheel while holding down the right-click (especially useful during sessions where many tabs are open within the same window)
• Close Tab - holding down the right-click and making an L-shape movement.
• True Zooming - holding down the CTRL key while using the scroll wheel. Rolling up enlarges the page by 10% increments, and vice versa.

The tools relating to browsing and email functions are organized within Opera Panels. Additionally, users may download additional tools or create their own.^[4]

• Bookmarks - list of all bookmark folders and the bookmarks they contain
• Mail - serves as access point for email accounts and news feeds
• Contacts - serves as an email address book.
• History - provides a log of all pages accessed, in chronological order, starting with the most recent.
• Links - list of links available in the current page.
• Notes - allows the user to copy and paste content into a built-in text editor. As the name implies, this tool is aimed towards note-taking tasks.
• Info - desplays page-specific information, including its MIME type, local cache, size, security information, and encoding.
• Windows - provides a summary for all tabs and windows open during an Opera session.
• Transfers - simplified view of current transfers in the download manager
• Widgets - list of installed widgets

Opera lets the user control whether web sites can open pop up windows. By default Opera blocks all unrequested popups, but can work in a variety of different ways, such as opening a pop-up as a background window, or only blocking pop-ups when they do not result from a user action like clicking on a link. Windows that have been blocked may be later opened at the user's discretion. Additionally, this behavior may be set on a per-site basis.

Since: Opera 4, released June 28, 2000

Opera provides quick access to a variety of search engines and commerce sites, via the use of search plugins. Many search plugins are included with the browser, but they can also be user-defined or installed from an external sources. Opera also allows a user to translate a paragraph or look for meaning of a word directly by a right mouse click.

A user can have access to any Search Engine without opening the corresponding page by typing a specified character (or series of characters) in the address bar, followed by the search string. Previously these identifier characters/search engine pairs could be specified only by editing the search.ini file manually. Since Opera 9, the user can Right Click in a Search Field on a website and then use the CREATE SEARCH option. The Search Engine will be listed in Opera in the future.

For example, Opera has a pre-set shortcut for using the Google search engine: "g." Therefore, if a user typed "g wikipedia" directly into the address bar, Opera performs a Google search for Wikipedia. Although this feature had already been implemented in pre-release versions of Netscape earlier the same year ^[5], Opera managed to release a stable version before Netscape did.

Since: Opera 9.5, released June 12, 2008

Words typed in the address bar perform full-text search in the browser cache. That allow a user to find the text in a page previously accessed.

Since: Opera 4, released June 28, 2000

Opera allows the user to save a collection of open pages as a session. This set of pages can then be opened later in a new Opera window or inserted into the current one. Opera can also be set up to start with the pages that were open when the browser was last closed. A saved session includes the independent history of each page and the settings each page had, such as scrolling position, images on/off, etc. This has been particularly helpful when a browser window has been accidentally closed or a personal computer has frozen. If that setting option is chosen, the browser will reopen with the recovered session.

Each session is saved in a text file that can be transferred to another computer via mail or otherwise.

Since: Opera 9.2, released April 11, 2007

Opera 9.20 has "Speed Dial Browsing". The "Blank Page" when a new tab is opened is replaced with a page with nine slots which the user can set to contain live webpage bookmarks. This feature is based on the speed dial browsing in Opera Mini^[6]. Opera 10 increases the number of speed dial entries to 25, and allows for larger and widescreen display layouts.

Since: Opera 4, released June 28, 2000^[7]

Opera supports tabbed browsing and has a true multiple document interface. This means multiple web pages can be opened within the same application window and resized, moved, tiled and cascaded like normal application windows in the operating system.

In subsequent years the default settings have changed from MDI to the simpler concept of tabs. Since version 6.0, Opera offers users the choice of three modes: Tabs, MDI, and SDI (No tabs).

The tabbing features available in the current release include:

• An actual, visible "New Tab" button to aid in usability
• Thumbnail preview for each tab that also provides META information
• Cascading, rearranging and tiling of tabs
• Individual "X" close buttons on each tab
• Tabs can be "locked," in order to prevent accidental closings
• Option of duplicating tabs - both history and settings
• Tabs can be separated and opened in new frames
• Indicator for page-loading progress

Since Opera 9, a thumbnail preview of a tab is shown when hovering the cursor over it.

Since: Opera 7, released January 28, 2003

Opera has a "trash can" button, which allows the user to retrieve blocked pop-ups or a tab closed earlier in the same session. A tab restored from the "trash can" retains its original settings (e.g. zoom level) and history. The list of blocked pop-ups or deleted tabs is kept until the user manually empties the "trash can" or the session is closed and can be used as a temporary bookmark during the session.

Closed tabs can also be recovered - in the reverse sequence in which they were closed - simply by pressing the common "undo" shortcut CTRL-Z.

In addition to the web browser, the other main component in the desktop versions of the Opera suite is the Opera Mail e-mail client. Opera Mail supports regular POP and SMTP mail as well as IMAP. It also has an Address book. Opera Mail also features a newsreader and a newsfeed reader for RSS and Atom, as well as an IRC client for online chat.

Since: Opera 9.50, released June 12, 2008

This feature lets users save bookmarks, notes, the Personal Bar and Speed Dial settings to the online "Opera Link" service. These preferences can be saved online and then be synchronized with another Opera browser, such as a copy of Opera Mini running on a mobile phone.

Users have the option of defining the appearance and functionality of nearly every item on the UI. Personal preferences for buttons and menus can be arranged with "drag and drop," while access to .ini files allows one to create, define, or redefine tools and functions

Opera supports customized user interfaces themes, allowing users to change the location and style of toolbars, buttons and menus. A drag and drop functionality allows the user to easily place links and buttons on toolbars. Many user-created themes, ranging from color changes to OS adaptations can be downloaded and installed with a few clicks thanks to the built-in automatic installer.

Opera also provides drop down toolbars that display different menus for relevant tasks when needed. For example, any activity in the address bar will open up the "start" toolbar, which provids access to address buttons, such as history or bookmarks. Additionally, another toolbar, "view," contains a zooming function.

Advanced users also have the option of directly accessing the .ini files that define the appearance of the browser. In doing so, users can actually create new menus and buttons, or modify existing ones.

Opera allows the user to use animated GIF images in custom skins.^[8]

Since: Opera 8, released April 19, 2005

Opera supports User JavaScript extensions. Those scripts execute when pages are loaded and are used to enhance site functionality. UserJS.org was the unofficial central repository for Opera User JavaScripts, but currently it's inactive. Userscripts.org lists scripts designed for the Greasemonkey Firefox extension, but many of them also work with Opera. Users may find useful user scripts shared at Opera's Community forums.

Widgets - small standalone applications sitting on top of the browser.

The Opera Software company claims that Opera is "the fastest browser on Earth."^[9] Third-party speed tests showed that Opera 9.01 performed faster than any other browser in 4 out of 7 speed tests on Microsoft Windows and Mac OS X and 3 out of 7 tests on Linux. Its strongest point by far was JavaScript execution, performing about twice as fast as the other browsers.^[10]

According to Secunia, Opera 9.x has had 4 security vulnerabilities, all of which are currently patched.^[11] These figures are better than those of Firefox 2.0.x (1 of 2 advisories unpatched, 1 of 11 vulnerabilities unpatched),^[12] Internet Explorer 7.x (3 out of 4 advisories unpatched, 3 of 5 vulnerabilities unpatched.),^[13] and Safari 2.x (4 of 6 advisories/vulnerabilities unpatched).^[14] The differences are more apparent when comparing older releases: Opera 8.x (All 15 advisories), Firefox 1.x (35 of 39 advisories patched), IE 6.x (91 of 110 advisories patched), and Safari 1.x (14 of 15 advisories patched).

Opera can be configured to use proxy servers. It has a built-in cookie editor and cache viewer. Also, a password management tool known as the Wand is integrated into the browser. Every page with a password form gives the user the option of storing the password for later use. To enhance usability, when a user re-visits these pages, the password field will highlight yellow to indicate that one only needs to use the Wand to continue.

Additionally, users have the option of setting a master password for use of the browser. This option is intended to protect against unauthorized tampering or access to stored passwords.

Beginning with the release of Opera 9.1, users can click on a button embedded into the address bar for any particular page to see a security assessment, including information about available SSL or TLS certificates. This tool is directly tied to Phishtank, thereby serving as a phishing filter as well as real-time fraud protection.^[15]

Fraud protection (Introduced in Opera 9.1) is a real-time security feature. Opera tests sites, that you navigate to, and checks them with the PhishTank database entries to see if they are "Verified" or "Fraud". This feature is disabled by default^[16], however, with release of version 9.5 it became enabled by default.

Opera includes developer tools similar to Firebug and the Internet Explorer Developer Toolbar.^[17]

In version 9.5, Opera introduced Dragonfly, a full-fledged online debugging tool, that allows debugging of the HTML DOM, Javascript, CSS and much more. For example, a user can set breakpoints, alter scripts on-the-fly and execute statements in the current environment from a console. Opera's implementation of the developer tools allows remote debugging, which is the ability to debug, from a desktop Opera instance, a webpage running anywhere, like a mobile device or another computer. Opera Dragonfly is included in versions 9.5 and up.

Since version 3.5, Opera has supported CSS, and Håkon Wium Lie, one of the inventors of CSS, is the CTO at Opera.^[18] Up to 6.0 Opera supported most common web standards, Netscape plugins and some other recent standards such as WAP and WML for wireless devices, but its implementation of advanced ECMAScript (better known as "JavaScript") and the HTML Document Object Model was poor.

Version 7.0 introduced the faster and more powerful Presto layout engine (which is also incorporated into Macromedia Dreamweaver, now owned by Adobe Systems, to render web graphics). This version supports the standards of older versions and has almost full support for the HTML DOM.

Version 8.0 introduced support for Scalable Vector Graphics (SVG) 1.1 Tiny. This marked the first major web browser to natively support some form of SVG.^[19] Opera has a presentation mode called Opera Show, which allows the use of a single HTML or XML document for large-screen presentations, and web browsing.

Version 9.0 is the first browser for Microsoft Windows that passes the Acid2 test, proving robustness of its CSS and HTML implementation. This version adds XSLT and improves SVG to 1.1 Basic level.

Technologies implemented/improved in Opera 9:

• XSLT, XPath
• SVG/1.1 Basic
• TLS/1.1

Beta versions of Opera 9 included an Easter egg that, when triggered,^[20] affects the Acid2 test. After the page has been open for a while, the eyes of the smiley will follow the cursor around and when the user clicks on the eyes, a JavaScript alert will read "Because just passing is not enough ;)".^[21] The changes to the Acid2 code were applied using Opera's browser.js feature, and remain available in a separate User JavaScript file.^[22]

Common compatibility problems are caused by websites not following standards or using outdated methods for detecting the browser being used. Websites are sometimes tested only with Internet Explorer and fail to work correctly with other browsers.

To cope with outdated detection methods or poorly built websites, Opera enables users to change the information that is sent to websites to identify what kind of browser is being used -- known as the user-agent. In previous years, Opera came preconfigured to partially "cloak" itself as Internet Explorer, but still included the word "Opera" in the user-agent information allowing the browser to be counted in web statistics. As websites modernized themselves and Opera 9 became more compatible with IE code, Opera began to use its own identification by default.

Later versions of Opera offer a limited method of cloaking, such as the ua.ini file. The ua.ini file does not allow the user to write arbitrary user-agent strings, but rather it allows selections from a pre-defined range including Mozilla and Internet Explorer. If needed, Opera can mask completely as Internet Explorer or Mozilla, leaving out the reference to Opera in the UA string and Javascript objects. Some sites test only for objects that are not present in Opera.

Version 8 of Opera introduced a further provision for dealing with faulty coding, by providing a set of scripts in BrowserJS that rewrites known broken pages as they are being opened. The closely-related UserJS (similar to Mozilla's Greasemonkey), allows users to run their own code at various times in the processing of a page. These techniques have allowed many popular but incompatible sites to be used fully with Opera. ^[23]

Opera periodically updates itself with the latest version of BrowserJS and ua.ini ^[24].

It is notable in the face of criticisms of rendering accuracy, that Opera 9.0, 10.00 and 10.10 pass the Acid2 and Acid3 rendering tests by the Web Standards Project, which are designed to test compliance with the latest HTML, CSS and other web standards.^[25] Internet Explorer 7 adoes not pass this test.