Mozilla Firefox Tips and Tricks


Last Updated for Firefox 31.2.0

Mozilla Firefox is a fast, easy, and powerful web browser, brought to us by the good folks at the Mozilla Foundation.  If you're reading this page, then you're probably already familiar with Firefox; so, I won't spend much time on an introduction.  Just for reference, here are a few important/useful links:

This page is intended to provide information on a few Firefox tricks that I personally find invaluable.  For additional tips and tricks, please visit the links above.

Note:  Many of the tips on this page assume that you are familiar with editing Firefox configuration files.  Please see MozillaZine's Editing Configuration page if you need more information.

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Firefox Extensions - Mandatory

Here are a few Firefox extensions that I consider essential for any Firefox installation.

Adblock Plus  (home page)

The Adblock Plus extension can strip annoying advertisements out of web pages, including Flash and Java applets, and also help prevent pop-ups.

Adblock Plus: Element Hiding Helper  (home page)

This Adblock companion extension adds functionality to selectively disable specific annoying or obtrusive elements on a given website.

Cookie Monster

Cookie Monster provides a great deal of additional cookie-related management functions to Firefox, allowing blacklisting cookies by default with an easy interface to quickly enable both first and third party cookies for a given site, permanently or temporarily, with just a couple clicks.

Copy As Plain Text  (home page)

Copy As Plain Text provides additional options for copying text from web pages.  For example, you can copy a block of text as plain or unformatted to make it easier to paste into other applications such as OpenOffice.


Mozilla developers made the incredibly stupid decision to restrict in-page search (ie., the find bar) to each individual tab, rather than allowing one search pattern to be used across multiple tabs. This means that if you open multiple tabs and want to search for a particular pattern, you need to retype the search phrase into each and every tab before search. Want to search for something else? You'll need to type the new phrase into each and every tab again. GlobalFindBar restores the previous functionality to let you enter your search phrase once, then simply switch to and search each additional tab.

Greasemonkey  (home page)

The Greasemonkey extension allows users to add custom scripts to change the behavior of any web page.  Many pre-written scripts can be found at

The following are my personal favorites.

  • Autocomplete - Always enables autocomplete on forms and input elements; used for forcing Firefox to remember password even on websites that disable autocomplete; original source no longer exists, here's a mirror
  • Better Amazon - Makes viewing product pages on Amazon much easier by providing collapsible sections and other features
  • Check Range (home page) - Allows selection of multiple checkboxes at once
  • Disable Targets - Prevent links for opening in new windows (eg., target='blank'), instead forcing them to follow your browser preferences; also prevents new windows caused by the javascript onclick property
  • Google Image Relinker - Rewrites links to point directly to source image; My modified version adds a link to the original website below each image
  • GoogleMonkeyR - Allows customization of Google search results, including removing tracking links
  • Image Hoster Skip Page - Skips the preview page for common image hosting websites and redirects to the full-sized image; My custom version fixes ShareNXS support and fixes ImageBam inconveniences
  • Linkify Plus (home page) - Transforms plaintext hyperlinks and e-mail address into valid links

HTTPS Everywhere

Enable encrypted automatically on sites known to support SSL. Note: This extension can and does break some sites that do not support SSL gloablly. If a site seems broken, try disabling this extension temporarily for troubleshooting.

keyconfig  (home page)

keyconfig allows you to change keyboard shortcuts. Configuration can be difficult, so be sure to check out the examples.

NextPlease  (home page)

NextPlease is a highly configurable extension that allows you to jump to next and previous links on multi-page articles, search results, or forum posts using keyboard shortcuts or toolbar buttons.

Proxy Selector

Proxy Selector lets you configure and easily switch between multiple proxy servers.

Status-4-Evar  (home page)

Status-4-Evar reimplements the browser status bar removed in Firefox 4.0 with additional flexibility.

tabse closebutton restored

Firefox developers removed the option to have a single tab close button in version 31. This extension restores that functionality.

Uppity  (home page)

Uppity allows easy navigation "up" a web directory, domain, query string, etc.

Firefox Extensions - Optional

These Firefox extensions are also quite useful, but are a bit more specialized and thus only applicable for certain installs.


Abduction! allows you to save any website, or part of a website, to an image file.  Rather than taking a snapshot of the visible window, it renders the entire page and exports it to an image.

Export Cookies

The Export Cookies extension allows you to export all saved Firefox cookies to an external file, which can then be loaded in another application (such as wget) to download content using the currently active credentials.

FireBug  (home page)

FireBug is an integrated JavaScript, CSS, HTML, and Ajax debugger for Firefox, including an error console, command line, and inspectors

Precise Clear History

Precise Clear History is pretty much exactly what it sounds like - it extends the clear history menu with additional options to clear items before, after, or between specific dates. Useful for easily clearing out all content greater than 30 days old, for example.

Print Edit

Print Edit allows editing web pages in the print preview view to remove or reformat sections of a website not wanted/needed in a printout.

Snap Links Plus  (home page)

Snap Links Plus allows you to select and act on multiple links at once.  Actions can be changed dynamically to either open all links in new tabs, download all links, etc.

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It's possible to customize how Firefox looks and feels by creating custom userContent.css and userChrome.css files.  userContent.css overrides how Firefox renders web pages, and userChrome.css overrides how Firefox renders itself.  For more details and examples, see the Customizing Mozilla link in the introduction.

userChrome.css - these styles modify Firefox's widgets

/* set width of search bar to 20em */
#search-container, #searchbar {
-moz-box-flex: 0 !important;
max-width: 20em !important;
width: 20em !important;

/* always display the go button */
#urlbar[pageproxystate="valid"] > #urlbar-go-button {
visibility: visible !important;

/* remove bookmark star button - removed in 31
#star-button {
display: none !important;
} */

/* allow keywords when adding a bookmark */
#editBMPanel_keywordRow {
visibility: visible;
#editBMPanel_tagsSelector[collapsed="true"] {
display: none !important;

/* reduce minimum tab width to fit more tabs on screen */
.tabbrowser-tab:not([pinned]) {
min-width: 70px !important;

/* never trim preview URLs */
statuspanel {
max-width: 100% !important;

/* hide UI elements */
#context-blockimage, #context-bookmarklink, #context-bookmarkpage,
#context-setDesktopBackground, #context-sendaudio, #context-sendvideo,
#context-sendimage, #context-sendlink, #context-sendpage,
#context-back, #context-forward, #context-reload, #context-stop,
#printedit-contentmenu {
display: none !important;

/* fix bug in Linux support, loading icon not being animated */
.tab-throbber[progress] {
list-style-image: url("loading.png") !important;

userContent.css - these styles modify Firefox's web page rendering

/* Change cursor for JavaScript links */
a[href^="javascript:"] {
cursor: move;

/* Make monospaced text readable */
code, code *, pre, pre * {
font-family: "DejaVu Sans Mono", sans-serif, monospace !important;
font-size: 9pt !important;

/* Fix transparent images */
@namespace url(;
body > img.decoded{
background-color: transparent !important;

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Firefox offers literally hundreds of possible options and settings, and as you can imagine taking the time to review all of these setting on each and every install can become quite tiresome.  To solve this problem, Firefox allows users to set their personal preferences in the user.js file in their profile directory (for more info on user.js, see the links in the introduction).

user.js settings have been fairly well documented throughout the web, but here are the settings that I use in my own file.

user.js - these preferences are hardcoded and never change

// Static Mozilla User Preferences

// This file always overrides preferences set within the browser (prefs.js)

// Cache and Memory preferences
user_pref("browser.cache.disk_cache_ssl", false); //don't cache SSL pages
//user_pref("image.mem.decodeondraw", false); //render images on load
//user_pref("image.mem.max_ms_before_yield", 100);//spend more time loading images
user_pref("image.mem.min_discard_timeout_ms", 480000); //slow bg tab discarding

// Extensions and Plugins
user_pref("extensions.alwaysUnpack", true); //unpack extensions automatically
user_pref("extensions.autoDisableScopes", 8); //don't disable silent extensions
user_pref("plugins.notifyMissingFlash", false); //don't notify
user_pref("plugin.disable_full_page_plugin_for_types", "application/pdf,audio/mpeg"); //prompt to download/open pdf, mp3, etc. files

// Javascript and Pop-ups
user_pref("dom.disable_open_click_delay", 3000); //increase block length
user_pref("dom.disable_window_open_feature.close", true);
user_pref("dom.disable_window_open_feature.menubar", true);
user_pref("dom.disable_window_open_feature.minimizable", true);
user_pref("dom.disable_window_open_feature.scrollbar", true);
user_pref("dom.disable_window_open_feature.titlebar", true);
user_pref("dom.disable_window_open_feature.toolbar", true);
user_pref("dom.popup_maximum", 5); //max popups from single page

// Miscellaneous
user_pref("browser.altClickSave", true); //re-enable saving w/ alt-click
user_pref("browser.feeds.showFirstRunUI", false); //disable initial RSS intro
user_pref("browser.rights.3.shown", true); //don't show EULA
user_pref("browser.pagethumbnails.capturing_disabled", true);//no page thmbnails
user_pref("browser.showQuitWarning", true); //prompt to save session on exit
user_pref("browser.slowStartup.notificationDisabled", false); //no slow notice
user_pref("browser.startup.homepage_override.mstone", "ignore"); //no upg. pages
user_pref("mozilla.widget.raise-on-setfocus", false); //disable focus stealing
//user_pref("media.webaudio.enabled", true); //enable webaudio API (def. in 25)

// Network and Proxy
user_pref("network.http.phishy-userpass-length", 20); //allow user:pass syntax
user_pref("network.http.pipelining", true); //enable HTTP pipelining
user_pref("network.http.pipelining.ssl", true); //enable HTTPS pipelining
user_pref("network.http.proxy.pipelining", true); //enable HTTP proxy pipelining
user_pref("network.prefetch-next", false); //disable prefetch hinting

// Privacy and Security
user_pref("browser.safebrowsing.enabled", false); //disable safe browsing
user_pref("browser.safebrowsing.malware.enabled", false);
user_pref("browser.xul.error_pages.expert_bad_cert", true); //unhide exception
//user_pref("", "6000");
user_pref("security.dialog_enable_delay", 300); //shorten button disable pause
user_pref("social.enabled", false); //disable social integration
user_pref("social.remote-install.enabled", false); //disable social integration
// Disable unsafe ciphers/protocols
user_pref("security.tls.version.min", 1); // disable SSLv3
//user_pref("security.ssl3.rsa_rc4_128_md5", false);
//user_pref("security.ssl3.rsa_rc4_128_sha", false);
//user_pref("security.ssl3.ecdh_ecdsa_rc4_128_sha", false);
//user_pref("security.ssl3.ecdh_rsa_rc4_128_sha", false);
//user_pref("security.ssl3.ecdhe_ecdsa_rc4_128_sha", false);
//user_pref("security.ssl3.ecdhe_rsa_rc4_128_sha", false);
// Disable potentially unsafe ciphers
//user_pref("security.ssl3.ecdh_ecdsa_des_ede3_sha", false);
//user_pref("security.ssl3.ecdh_ecdsa_rc4_128_sha", false);
//user_pref("security.ssl3.ecdh_rsa_des_ede3_sha", false);
//user_pref("security.ssl3.ecdhe_ecdsa_des_ede3_sha;true", false);
//user_pref("security.ssl3.ecdhe_rsa_des_ede3_sha", false);

// Source Code
user_pref("view_source.editor.external", true); //use external editor
user_pref("view_source.editor.path", "{EDITOR}"); //editor
user_pref("view_source.wrap_long_lines", true); //enable line wrapping

// Spellchecker
user_pref("extensions.spellcheck.inline.max-misspellings", 2500);
user_pref("layout.spellcheckDefault", 2); //spellcheck all input fields
user_pref("spellchecker.dictionary", "en_US"); //specify dictionary

// Tab Management
//user_pref("browser.tabs.animate", false); //disable tab animations
user_pref("browser.tabs.insertRelatedAfterCurrent", false); //load new tabs last

// Window and URL Bar Management
user_pref("browser.preferences.instantApply", true);
user_pref("", false); //disable search suggestions
//user_pref("browser.tabs.drawInTitlebar", false); //always show title bar
user_pref("browser.urlbar.trimURLs", false); //always show protocol prefix
user_pref("clipboard.autocopy", false); //don't autocopy highlighted text
user_pref("editor.singleLine.pasteNewlines", 3); //accept multiline pasted URLs
user_pref("general.warnOnAboutConfig", false); //don't display warning prompt
user_pref("middlemouse.contentLoadURL", false); //don't load URL on middle-click
user_pref("privacy.popups.showBrowserMessage", false); //disable popup bar

// Extensions - force disable update popups
user_pref("extensions.adblockplus.currentVersion", "9999");
user_pref("extensions.greasemonkey.version", "9999");

prefs.js - this sets default preferences that can be changed

// Changes to this file can be overridden by the browser

// Horrible hack to set toolbar icon order
user_pref("browser.uiCustomization.state", "{\"placements\":{\"PanelUI-contents\":[\"edit-controls\",\"zoom-controls\",\"new-window-button\",\"privatebrowsing-button\",\"add-ons-button\",\"preferences-button\",\"print-button\",\"printedit-buttonmenu\",\"history-panelmenu\",\"find-button\",\"developer-button\"],\"status4evar-status-bar\":[\"status4evar-status-widget\",\"status4evar-progress-widget\",\"status4evar-legacy-widget\"],\"addon-bar\":[\"addonbar-closebutton\",\"status-bar\"],\"PersonalToolbar\":[\"personal-bookmarks\"],\"nav-bar\":[\"tb-uppity\",\"urlbar-container\",\"feed-button\",\"cookiemonster-status\",\"abp-toolbarbutton\",\"greasemonkey-tbb\",\"https-everywhere-button\",\"firebug-badged-button\",\"downloads-button\",\"mproxy-element-button\",\"webrtc-status-button\",\"social-share-button\"],\"TabsToolbar\":[\"appmenu-toolbar-button\",\"tabbrowser-tabs\",\"new-tab-button\",\"fullscreen-button\",\"alltabs-button\",\"tabs-closebutton\"],\"toolbar-menubar\":[\"menubar-items\"]},\"seen\":[\"status4evar-legacy-widget\",\"abp-toolbarbutton\"],\"dirtyAreaCache\":[\"status4evar-status-bar\",\"addon-bar\",\"PersonalToolbar\",\"nav-bar\",\"TabsToolbar\",\"PanelUI-contents\",\"toolbar-menubar\"],\"newElementCount\":0}");

// Bookmarks and History
user_pref("browser.places.smartBookmarksVersion", 7); //todo - update to 7?
//user_pref("browser.places.updateRecentTagsUri", false);

// Download Manager
user_pref("", "{OUTDIR}");
user_pref("", 2); //auto save to download.dir
user_pref("", "{OUTDIR}");
user_pref("", false); //no dload history
//user_pref("", true);
user_pref("", 1); //do not resume on start
user_pref("", 0); //remove on completion
user_pref("", false); // do not run scan
user_pref("", false);
user_pref("", false);
user_pref("", true); //don't show download popup
user_pref("", 1); //only save page HTML

// Miscellaneous
user_pref("accessibility.typeaheadfind", false); //press slash first
user_pref("browser.customizemode.tip0.shown", true); //don't show cust. popup
user_pref("browser.migration.version", 22);
user_pref("", true); //always verify default
user_pref("browser.syncPromoViewsLeftMap", "{\"passwords\":0,\"addons\":0,\"bookmarks\":0}");//no sync prmpt
user_pref("browser.zoom.full", false); //revert to text-based zoom

// Network and Proxy
user_pref("network.proxy.autoconfig_url", "");
user_pref("network.proxy.http", "localhost");
user_pref("network.proxy.http_port", 3128);
user_pref("network.proxy.share_proxy_settings", true);
user_pref("network.proxy.ssl", "localhost");
user_pref("network.proxy.ssl_port", 3128);
user_pref("browser.startup.homepage", "");
user_pref("", 0); //start with blank page

// Privacy and Security // todo - review
user_pref("", false);
//user_pref("network.cookie.cookieBehavior", 1); //only from originating server
//user_pref("network.cookie.lifetimePolicy", 1); //prompt to accept
user_pref("network.cookie.cookieBehavior", 2); //disable; use cookie monster
user_pref("network.cookie.prefsMigrated", true); //don't migrate cookies
user_pref("privacy.donottrackheader.enabled", true); //opt out of tracking
user_pref("privacy.cpd.cookies", false); //do not clear saved cookies
user_pref("privacy.cpd.formdata", false); //do not clear saved form data
//user_pref("privacy.cpd.offlineApps", true); //clear offline apps data
//user_pref("privacy.sanitize.migrateFx3Prefs", true); //don't modify prefs
user_pref("privacy.sanitize.timeSpan", 0); //clear all data by default
//user_pref("toolkit.telemetry.prompted", 2); //disable perf monitoring prompt
//user_pref("toolkit.telemetry.rejected", true); //disable perf. monitoring
//user_pref("datareporting.healthreport.uploadEnabled", false); //no data upload
user_pref("datareporting.policy.dataSubmissionPolicyBypassAcceptance", true); //allow health report upload w/ no prompt

// SSL Certificates
user_pref("security.default_personal_cert", "Select Automatically");

// Tab Management
user_pref("browser.fullscreen.autohide", false); //always show tab bar
user_pref("browser.newtab.url", "about:blank"); //disable fancy new tab page
user_pref("browser.tabs.loadBookmarksInBackground", true); //new tabs in backg.
user_pref("browser.tabs.warnOnOpen", false); //don't warn on opening mult. tabs

// Window, Tab, and URL Bar Management
user_pref("browser.preferences.advanced.selectedTabIndex", 1); //preselect tab
user_pref("browser.tabs.drawInTitlebar", false); //always show title bar
user_pref("extensions.ui.lastCategory", "addons://list/extension");//inst. exts.
user_pref("general.autoScroll", false);
user_pref("general.smoothScroll", false);

// FireBug
user_pref("extensions.firebug.addonBarOpened", true);
user_pref("extensions.firebug.key.shortcut.toggleInspecting", "");
user_pref("extensions.firebug.showCSSErrors", true);
user_pref("extensions.firebug.showCommentNodes", true);
user_pref("extensions.firebug.showFirstRunPage", false);
user_pref("extensions.firebug.showJSWarnings", true);
user_pref("extensions.firebug.showXMLErrors", true);
user_pref("extensions.firebug.toolbarCustomizationDone", true);

// GlobalFindBar
user_pref("extensions.jid0-GlobalFindBar@jetpack.winScope", 1);

// Greasemonkey
user_pref("extensions.greasemonkey.stats.prompted", true);
user_pref("extensions.greasemonkey.editor", "{EDITOR}");
user_pref("extensions.greasemonkey.scriptvals.", true);
user_pref("extensions.greasemonkey.scriptvals.", 2000000000);
user_pref("extensions.greasemonkey.scriptvals.", true);
user_pref("extensions.greasemonkey.scriptvals.", true);
user_pref("extensions.greasemonkey.scriptvals.", "");
user_pref("extensions.greasemonkey.scriptvals.", true);
user_pref("extensions.greasemonkey.showGrantsWarning", false);

// HTTPS Everywhere
user_pref("extensions.https_everywhere._observatory.popup_shown", true);
user_pref("extensions.https_everywhere.firstrun_context_menu", false);
user_pref("extensions.https_everywhere.toolbar_hint_shown", true);
user_pref("extensions.https_everywhere.RedHat", false); //breaks support site
user_pref(" (CAcert)", true);
user_pref("extensions.https_everywhere.rule_toggle.Deposit Files (partial)", false);
user_pref("extensions.https_everywhere.rule_toggle.Gentoo (partial)", true);
user_pref("extensions.https_everywhere.rule_toggle.Google APIs", false);
user_pref("extensions.https_everywhere.rule_toggle.Google Search", true);
user_pref("extensions.https_everywhere.rule_toggle.Google Services", false);
user_pref(" (partial)", false);
user_pref("extensions.https_everywhere.rule_toggle.Optimizely", true);
user_pref("extensions.https_everywhere.rule_toggle.ThinkGeek", false);
user_pref("extensions.https_everywhere.rule_toggle.Uservoice (partial)", true);
user_pref("extensions.https_everywhere.rule_toggle.Wikia", false);
user_pref("extensions.https_everywhere.rule_toggle.YouTube (partial)", false);

// Keyconfig
user_pref("keyconfig.main.focusChatBar", "!][][");
user_pref("keyconfig.main.key_netmonitor", "!][][");
user_pref("keyconfig.main.manBookmarkKb", "control shift][B][");
user_pref("keyconfig.main.nextplease0key", "!][][");
user_pref("keyconfig.main.Screenshoter_save_complete_key", "!][][");
user_pref("keyconfig.main.Screenshoter_save_selection_key", "!][][");
user_pref("keyconfig.main.sharePage", "!][][");
user_pref("keyconfig.main.showAllHistoryKb", "!][][");
user_pref("keyconfig.main.xxx_key__Focus Content", "control shift][F][][_content.focus();");
user_pref("keyconfig.main.xxx_key__Options", "control shift][O][][toOpenWindowByType('Browser:Options', 'chrome://browser/content/preferences/preferences.xul');");
user_pref("keyconfig.main.xxx_key__Reload Frame", "alt shift][R][][document.commandDispatcher.focusedWindow.document.location.reload();");
user_pref("keyconfig.main.xxx_key__Restart Firefox", "control shift][Q][][var os = Components.classes[\";1\"] .getService(Components.interfaces.nsIObserverService);\nvar cancelQuit = Components.classes[\";1\"] .createInstance(Components.interfaces.nsISupportsPRBool);\nos.notifyObservers(cancelQuit, \"quit-application-requested\", \"restart\");\nif (\nreturn;\nvar nsIAppStartup = Components.interfaces.nsIAppStartup;\nComponents.classes[\";1\"].getService(nsIAppStartup) .quit(nsIAppStartup.eRestart | nsIAppStartup.eAttemptQuit);][");
user_pref("keyconfig.main.xxx_key__Send Mail", "control][M][][loadURI(href=\"mailto:\");");

// NextPlease
user_pref("nextplease.allowcontextmenu", false);
user_pref("nextplease.allownumbershortcuts", false);
user_pref("nextplease.allowsubmit", true);
user_pref("nextplease.enable.firstkey", false);
user_pref("nextplease.enable.lastkey", false);
user_pref("nextplease.iskeycode.nextkey", false);
user_pref("nextplease.iskeycode.prevkey", false);
user_pref("nextplease.firstkeymodifier", "control");
user_pref("nextplease.keymodifier", "control");
user_pref("nextplease.lastkeymodifier", "control");
user_pref("nextplease.nextkey", 46);
user_pref("nextplease.numbermodifier", "control");
user_pref("nextplease.prevkey", 44);
user_pref("nextplease.prevkeymodifier", "control");

// Proxy Selector
user_pref("extensions.proxyselector.clear.cookies", false);
user_pref("extensions.proxyselector.display.context", false);
user_pref("extensions.proxyselector.display.statusbar", false);
user_pref("extensions.proxyselector.proxy.current", "None");
user_pref("", false);

// Snap Links Plus
user_pref("extensions.snaplinks.ActionInterval", 25);
user_pref("extensions.snaplinks.button", 1);
user_pref("extensions.snaplinks.SwitchToFirstNewTab", false);

// Status-4-Evar
user_pref("status4evar.addonbar.windowGripper", false);
user_pref("status4evar.advanced.showWarning", false);
user_pref("", false);
user_pref("status4evar.firstRun", false);
user_pref("status4evar.firstRun.australis", false);
user_pref("status4evar.migration", 5);
user_pref("status4evar.status", 3);
user_pref("status4evar.status.default", false);
user_pref("status4evar.status.linkOver", 3);
user_pref("", 50);
user_pref("status4evar.status.popup.invertMirror", true);

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