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accessibility, screenreaders

Learn about Firefox features that make the browser and content accessible to those who have low vision, no vision or limited ability to use a keyboard or mouse.

'''Firefox includes many features to make the browser and web content accessible to all users, including those who have low vision, no vision, or limited ability to use a keyboard or mouse.''' __TOC__ = Using a Keyboard = == Keyboard Shortcuts == A list of common keyboard shortcuts is available in [[Keyboard shortcuts - Perform common Firefox tasks quickly]]. == Always use the cursor keys to navigate within webpages == '''[[Advanced settings for accessibility, browsing, system defaults, network, updates, and encryption#w_accessibility|Always use the cursor keys to navigate within webpages]]''' allows you to move through web content as if you were inside a read-only editor. You can use the keyboard to select web content and copy it to the clipboard. You can press {key F7} at any time to turn this feature on or off. When you press {key F7}, Firefox will ask if you really want to turn on this feature. You can disable this prompt by selecting '''Do not show this dialog again'''. == Search for text when I start typing == '''[[Advanced settings for accessibility, browsing, system defaults, network, updates, and encryption#w_accessibility|Search for text when I start typing]]''' allows you to quickly navigate to text or hyperlinks in a web page. This feature has two modes. Press {key /} and start typing to search all text on the current page, or press {key '} before your string to search hyperlinks only. Firefox will highlight matching text or hyperlinks as you type. The following keyboard shortcuts control this feature: * Type more characters to narrow your search. Firefox will highlight the next matching hyperlink or text or alert you that nothing matched. * Press {for win,linux}{key Ctrl}{/for}{for mac}{key command}{/for}+{key G} or {key F3} to find the next occurrence of your current search string. * Press {for win,linux}{key Ctrl}{/for}{for mac}{key command}{/for}+{key Shift}+{key G} or {key Shift}+{key F3} to find the previous occurrence of your current search string. * Press {key Backspace} to undo the last character you typed. Firefox will back up to the previously highlighted text. * Press {key Esc} to cancel a search. You can also cancel a search by changing focus, or simply waiting for the timeout. If this option is checked, you can start typing at any time to auto-start an inline search. By default auto-started searches look for all text on the page. You can still explicitly press {key '} or {key /} to start finding in one mode or the other. You can use this feature to get to buttons, text boxes and other form controls. Search for the text immediately before the form control you want and press {key Tab}. Pressing {key Tab} automatically exits the search and sets focus to the next form field or button after the highlighted text. == HTML Access Keys == On some web pages, keyboard shortcuts are assigned to different elements on the page. To move the cursor directly to one of these elements, press {for win,linux}{key Shift}+{key Alt}{/for}{for mac}{key Ctrl}{/for}+''AccessKey''. * Which key ''AccessKey'' is depends on the website. It is determined by the website author, not Firefox. = Using a Mouse = == Mouse Shortcuts == A list of common mouse shortcuts is available in [[Use mouse shortcuts to perform common tasks in Firefox]]. = Page Zoom = You can zoom in and out of web pages including images with the following keyboard shortcuts: * Press {for win,linux}{key Ctrl}{/for}{for mac}{key command}{/for}+{key +} to display the web page one size larger. * Press {for win,linux}{key Ctrl}{/for}{for mac}{key command}{/for}+{key -} to display the web page one size smaller. * Press {for win,linux}{key Ctrl}{/for}{for mac}{key command}{/for}+{key 0} (zero) to display the web page at its normal size. For other ways to zoom in and out a web page, see [[Font size and zoom - increase the size of web pages]]. = Fonts and Colors = See [[Change the fonts and colors websites use]] for detailed instructions on choosing your preferred font styles and colors. == Overriding Page Fonts == Some websites may display text in fonts that are difficult to read, and other sites may rely on the browser's default fonts. You can set your default fonts by opening the {for win}Options{/for}{for mac,linux}Preferences{/for} window, selecting the {menu Content} panel, and selecting a default font and size in the ''Fonts & Colors'' section. You can specify default fonts for different styles, including serif, sans-serif, and monospace by clicking the {button Advanced…} button. However, many web pages specify their own fonts, so your choices will have no effect on such pages. To override the fonts defined by such pages, uncheck the '''Allow pages to choose their own fonts, instead of my selections above''' {for win}option{/for}{for mac,linux}preference{/for}. Note that some web pages may display incorrectly depending on your choice of a default font. == Setting a Minimum Font Size == Some websites may display text which is too small to read comfortably. To make such pages easier to read, you can set a minimum font size. On web pages that try to display text smaller than this size, Firefox will enlarge the text to your chosen size. To set a minimum font size, open the {for win}Options{/for}{for mac,linux}Preferences{/for} window, select the {menu Content} panel, and click the {button Advanced…} button in the ''Fonts & Colors'' section. You can specify a minimum font size from the dropdown menu. Note that some web pages may display incorrectly depending on your choice of a minimum font size. == Resizing Page Text == You can change the size of text on any web page with Text Zoom you can select as follow: # {for win7,win8}Press the {key Alt} key to temporarily bring up the traditional Firefox menus.{/for} {for win,linux}At the top of the Firefox window{/for}{for mac}On the menu bar{/for}, click the {menu View} menu, then go to {menu Zoom}. #Select {menu Zoom Text Only}, which will make the controls only apply to text, not images. The following keyboard shortcuts control text size when Text Zoom is selected: * Press {for win,linux}{key Ctrl}{/for}{for mac}{key command}{/for}+{key +} to increase the text size. * Press {for win,linux}{key Ctrl}{/for}{for mac}{key command}{/for}+{key -} to decrease the text size. * Press {for win,linux}{key Ctrl}{/for}{for mac}{key command}{/for}+{key 0} (zero) to reset the text size to the web page's default size. Note that some web pages may display incorrectly if you increase or decrease the text size. For other ways to zoom in and out text of a web page, see [[Font size and zoom - increase the size of web pages]]. == Overriding Page Colors == Some websites may display text and background colors that are difficult to read, and other sites may rely on the browser's default colors. You can set your default colors by opening the {for win}Options{/for}{for mac,linux}Preferences{/for} window, selecting the {menu Content} panel, and clicking the {button Colors…} button in the ''Fonts & Colors'' section. You can set default text and background colors, as well as default colors for visited and unvisited hyperlinks. You can also specify whether hyperlinks should be underlined. However, many web pages set their own colors, so your choices will have no effect. To override the colors defined by web pages, uncheck the '''Allow pages to choose their own colors, instead of my selections above''' {for win}option{/for}{for mac,linux}preference{/for}. == Using a High Contrast Theme == Firefox automatically detects if you are using a High Contrast theme and displays everything in your high contrast color scheme. This overrides all other other browser or web page settings, and it affects the Firefox interface itself (all menus, windows, and dialog boxes) and the content of any web page you visit. {for win} To use a High Contrast theme, go to {menu Start Menu}, select {menu Control Panel}, then {menu Accessibility Options}, finally {menu Display} and check the '''Use High Contrast''' option. {/for} = Controlling Web Content = == Blocking Pop-up Windows == See [[Pop-up blocker settings, exceptions and troubleshooting]] for information on blocking pop-up windows. == Turning Off Java Applets == Some web pages provide a rich interactive experience with Java™ applets. However, some users that rely on keyboard navigation may experience problems with some Java applets that automatically set focus and do not provide a way to break out of the applet and navigate to the rest of the web page. If this is a problem for you, you can disable Java by opening the add-on manager, selecting the {menu Plugins} panel, selecting the Java item(s) in the list, and then {for not fx23}clicking {button Disable}{/for}{for fx23}selecting {button Never Activate}{/for}. == Restricting JavaScript Behavior == {for not fx23} You can turn off JavaScript entirely by opening the {for win}Options{/for}{for mac,linux}Preferences{/for} window, selecting the {menu Content} panel, and unchecking '''Enable JavaScript'''. Some web pages rely on JavaScript and may not work properly if JavaScript is disabled. If you do not wish to disable JavaScript entirely, there are also a number of advanced JavaScript settings to restrict the behavior of scripts. Immediately after the '''Enable JavaScript''' checkbox, click the {button Advanced…} button to open the ''Advanced JavaScript Settings'' window. You can control whether scripts are allowed to move or resize existing windows, raise or lower windows, disable or replace context menus. {/for} {for fx23} JavaScript can be used to do things that some people don't like. For better control, you can install [https://addons.mozilla.org/firefox/search/?tag=privacy privacy extensions]. For more info, see [[JavaScript settings and preferences for interactive web pages]]. {/for} = Compatibility With Assistive Technologies = == Screen Reader== A screen reader is a software application that attempts to identify and interpret what is being displayed on the screen (or, more accurately, sent to standard output, whether a video monitor is present or not). This interpretation is then re-presented to the user with text-to-speech, sound icons, or a Braille output device. Screen readers are a form of assistive technology (AT) potentially useful to people who are blind, visually impaired, illiterate or learning disabled, often in combination with other AT, such as screen magnifiers. The above was adapted from Wikipedia under [http://creativecommons.org/licenses/by-sa/3.0/ creative commons]. Here are a [http://en.wikipedia.org/wiki/Comparison_of_screen_readers list of screen reader software] and links to common ones: {for win} *[http://www.nvda-project.org/ NVDA] *[http://www.screenreader.net/ Thunder] *[http://webanywhere.cs.washington.edu/ WebAnywhere] *[http://www.freedomscientific.com/ Jaws] (commercial) *[http://www.gwmicro.com/Window-Eyes/ Windows Eyes] (commercial) *[https://addons.mozilla.org/firefox/tag/screen%20reader Screen Reader Add-ons for Firefox] {/for} {for mac} *[http://www.apple.com/accessibility/voiceover/ VoiceOver] {for fx16}- Firefox now includes basic support for Voiceover. ([http://www.marcozehe.de/2012/04/30/initial-voiceover-support-now-in-firefox-nightly-builds-for-mac-os-x/ more info]){/for} *[http://www.assistiveware.com/proloquo.php Proloquo] *[http://webanywhere.cs.washington.edu/ WebAnywhere] *[https://addons.mozilla.org/firefox/tag/screen%20reader Screen Reader Add-ons for Firefox]. {/for} {for linux} *[http://webanywhere.cs.washington.edu/ WebAnywhere] *[http://projects.gnome.org/orca/ orca] *[https://addons.mozilla.org/firefox/tag/screen%20reader Screen Reader Add-ons for Firefox]. {/for} = Finding useful Links to do with accessibility = [http://accessfirefox.org Access Firefox website] contains many useful links. {for win} Freedom Scientific maintains a number of [http://www.freedomscientific.com/fs_support/User_Groups.asp mailing lists for JAWS users]. GW Micro maintains a number of [http://www.gwmicro.com/Support/Email_Lists/ mailing lists for Window Eyes users]. {/for} [[Template:ShareArticle|link=http://mzl.la/N0tsPN]]