Difference between revisions of "Firefox"

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[[Category:Web browser]]
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[[zh-CN:Firefox]]
[[Category:Web Browser]]
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{{Related articles start}}
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{{Related|Browser plugins}}
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{{Related|Firefox tweaks}}
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{{Related|Chromium}}
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{{Related|Opera}}
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{{Related articles end}}
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[https://www.mozilla.org/firefox Firefox] is a popular open-source graphical web browser from [https://www.mozilla.org Mozilla].
  
 +
== Installing ==
  
{{Article summary start}}
+
Firefox can be [[installed]] with the {{Pkg|firefox}} package.
{{Article summary text|Installing and troubleshooting the Firefox browser and plugins}}
+
{{Article summary heading|Related}}
+
{{Article summary wiki|Browser Plugins}}: Acquiring and installing plugins such as [[Flash]]
+
{{Article summary wiki|Firefox Tweaks}}: Configuration and modifications
+
{{Article summary end}}
+
  
[http://www.firefox.com Firefox] is a popular open-source graphical web browser from [http://www.mozilla.com Mozilla].
+
Other alternatives include:
  
== Installing ==
+
* {{App|Firefox Extended Support Release|long-term supported version|https://www.mozilla.org/firefox/organizations/|{{AUR|firefox-esr}} or {{AUR|firefox-esr-bin}}}}
The {{Pkg|firefox}} package can be found in the [[Official Repositories|official repositories]] and can be installed with [[pacman]].
+
* {{App|Firefox Beta|cutting-edge version|https://www.mozilla.org/firefox/channel/#beta|{{AUR|firefox-beta}} or {{AUR|firefox-beta-bin}}}}
 +
* {{App|Firefox Developer Edition/Aurora|for developers|https://www.mozilla.org/firefox/channel/#developer|{{AUR|firefox-aurora}}}}
 +
* {{App|Firefox Nightly|nightly builds for testing|https://nightly.mozilla.org/|{{AUR|firefox-nightly}}}}
 +
* {{App|Firefox KDE|Version of Firefox that incorporates an OpenSUSE patch for better KDE integration than is possible through simple Firefox plugins.|https://build.opensuse.org/package/show/mozilla:Factory/MozillaFirefox|{{AUR|firefox-kde-opensuse}}}}
 +
* On top of the different Mozilla build channels, a number of forks exist with more or less special features; see [[List of applications#Gecko-based]].
  
There are a number of language packs available if English is not your preferred language. To see a list of available language packs, try:
+
Here you can find an overview of Mozilla's [https://wiki.mozilla.org/Releases releases].
{{bc|$ pacman -Ss firefox-i18n}}
+
  
If Firefox does not anti-alias and/or hint your fonts, try to install {{AUR|ttf-win7-fonts}} (preferred) or {{AUR|ttf-ms-fonts}} and take a look at [[Font Configuration]].
+
There are a number of language packs available for Firefox, other than the standard English. Language packs are usually named as {{ic|firefox-i18n-languagecode}} (where {{ic|languagecode}} can be any language code, such as '''de''', '''ja''', '''fr''', etc.). For a list of available language packs see [https://www.archlinux.org/packages/?sort=&q=firefox-i18n&maintainer=&last_update=&flagged=&limit=100 this].
  
 
== Add-ons ==
 
== Add-ons ==
Firefox is well known for its large library of add-ons which can be used to add new features or modify the behavior of existing features of Firefox.  You can find new add-ons or manage installed add-ons with Firefox's "Add-ons Manager."
 
  
For a list of popular add-ons, see: [https://addons.mozilla.org/en-US/firefox/extensions/?sort=popular Mozilla's add-on list sorted by popularity].
+
Firefox is well known for its large library of add-ons which can be used to add new features or modify the behavior of existing features of Firefox. You can find new add-ons or manage installed add-ons with Firefox's "Add-ons Manager."
 +
 
 +
For a list of popular add-ons, see [https://addons.mozilla.org/firefox/extensions/?sort=popular Mozilla's add-on list sorted by popularity]. See also [[Wikipedia:List of Firefox extensions|List of Firefox extensions]] on Wikipedia.
 +
 
 +
== Configuration ==
 +
 
 +
Firefox exposes a number of configuration options. To examine them, enter:
 +
about:config
 +
in the Firefox address bar.
 +
 
 +
Once set, these affect the user's current profile, and may be synchronized across all devices via [https://www.mozilla.org/firefox/sync/ Firefox Sync]. Please note that only a subset of the {{ic|about:config}} entries are synchronized by this method, and the exact subset may be found by searching for {{ic|services.sync.prefs}} in {{ic|about:config}}.  Additional preferences and 3rd party preferences may be synchronized by creating new boolean entries prepending the config value with {{ic|services.sync.prefs.sync}}  ([https://developer.mozilla.org/en-US/docs/Archive/Mozilla/Firefox_Sync/Syncing_custom_preferences documentation] is still applicable.)  To synchronize the whitelist for the extension [https://addons.mozilla.org/en-US/firefox/addon/noscript/ NoScript]:
 +
services.sync.prefs.sync.capability.policy.maonoscript.sites
 +
The boolean {{ic|noscript.sync.enabled}} must be set to true to synchronize the remainder of NoScript's preferences via Firefox Sync.
 +
 
 +
Firefox also allows configuration for a profile via a {{ic|user.js}} file: [http://kb.mozillazine.org/User.js_file user.js] kept in the profile folder, usually {{ic|~/.mozilla/firefox/''some name''.default/}}. For a useful starting point, see e.g [https://github.com/pyllyukko/user.js custom user.js] which is targeted at privacy/security conscious users.
 +
 
 +
One drawback of the above approach is that it is not applied system-wide. Furthermore, this is not useful as a "pre-configuration", since the profile directory is created after first launch of the browser. You can, however, let ''firefox'' create a new profile and, after closing it again, [https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles#w_restoring-a-profile-backup copy the contents] of an already created profile folder into it.
 +
 
 +
Sometimes it may be desired to lock certain settings, a feature useful in widespread deployments of customized Firefox. In order to create a system-wide configuration, follow the steps outlined in [http://kb.mozillazine.org/Locking_preferences Locking preferences]:
 +
 
 +
1. Create {{ic|/usr/lib/firefox/defaults/pref/local-settings.js}}:
 +
pref("general.config.obscure_value", 0);
 +
pref("general.config.filename", "mozilla.cfg");
 +
2. Create {{ic|/usr/lib/firefox/mozilla.cfg}} (this stores the actual configuration):
 +
//
 +
//...your settings...
 +
// e.g to disable Pocket, uncomment the following line
 +
// lockPref("browser.pocket.enabled", false);
 +
 
 +
Please note that the first line must contain exactly {{ic|//}}. The syntax of the file is similar to that of {{ic|user.js}}.
  
 
== Plugins ==
 
== Plugins ==
''See: [[Browser Plugins]]''
+
 
 +
See the main article: [[Browser plugins]]
  
 
To find out what plugins are installed/enabled, enter:
 
To find out what plugins are installed/enabled, enter:
 
  about:plugins
 
  about:plugins
in the Firefox address bar. Or go to ''Addons'' from the main bar drop downs <!-- I use vimperator so I do not know what's the name --> and select the ''Plugins'' tab.
+
in the Firefox address bar or go to the ''Add-ons'' entry in the Firefox Menu and select the ''Plugins'' tab.
  
=== GNOME integration ===
+
=== GNOME Keyring integration ===
Install {{AUR|firefox-extension-gnome-keyring-git}} from the [[Arch User Repository|AUR]] to integrate Firefox 3.6.x with Gnome-keyring.
+
  
You can also install {{AUR|firefox-extension-firefoxnotify-git}} to get libnotify/notifyOSD integration.
+
Install {{AUR|mozilla-extension-gnome-keyring-git}} (all-JavaScript implementation) to integrate Firefox with [[GNOME Keyring]]. To make firefox-gnome-keyring use your login keychain, set extensions.gnome-keyring.keyringName to "login" (without the double quotes) in about:config. Note the lowercase 'l' despite the the keychain name having an uppercase 'L' in Seahorse.
 +
 
 +
=== KDE integration ===
 +
 
 +
{{Warning|1=Since GTK3 was updated to 3.20.x, there are several broken themes. Including '''Breeze''', the recommended theme for integration between KDE and GTK styles. Some of the issues are invisible scroll bars, no text highlight on selection, invisible checkboxes, among others. As a workaround while the themes are upgraded you can do the following after installing {{Pkg|kde-gtk-config}}, go to {{ic|System Settings}} -> {{ic|Application Style}} -> {{ic|GNOME Application Style (GTK)}} and choose in the '''Select a GTK3 Theme''' dropdown choose the '''Default''' theme, also make sure '''Show icons in GTK buttons''' and '''Show icons in GTK''' are checked. For further information on the compatibility issue above visit the [https://bbs.archlinux.org/viewtopic.php?pid=1619076 GTK3 3.20 upgrade thread] in the Arch Forums.}}
 +
 
 +
* To bring the KDE look to GTK apps (including Firefox), install {{Pkg|breeze-gtk}} and {{Pkg|kde-gtk-config}}. Afterwards, go to {{ic|System Settings}} -> {{ic|Application Style}} -> {{ic|GTK}}. Be sure to choose 'Breeze' in 'Select a GTK2/GTK3 Theme' and check 'Show icons in GTK buttons' and 'Show icons in GTK'.
 +
 
 +
* To use KDE's KPart technology with Firefox, by embedding different KDE file viewers into the browser, you can install {{Pkg|kpartsplugin}}.
 +
 
 +
* For integration with KDE’s mime type system and file dialogs, one can use {{AUR|firefox-kde-opensuse}} variant from AUR with OpenSUSE’s patches applied.
 +
 
 +
* Add-ons may provide some integration, such as [https://addons.mozilla.org/firefox/addon/kde-wallet-password-integratio/ KWallet integration], [https://addons.mozilla.org/firefox/addon/unityfox-revived/ Unityfox Revived], and [https://addons.mozilla.org/firefox/addon/plasmanotify/ Plasma notifications].
  
 
=== Dictionaries for spell checking ===
 
=== Dictionaries for spell checking ===
Right click in any text entry field and add the dictionary for the solicited language. Restart Firefox, and click in a text entry field again to enable spell checking.
 
  
Or get it from pacman:
+
To enable spell checking for a specific language right click on any text field and check the ''Check Spelling'' box. To select a language for spell checking to you have right click again and select your language from the ''Languages'' sub-menu.
pacman -Ss hunspell
+
  
=== Adding Firefox search engines ===
+
To get more languages just click ''Add Dictionaries...'' and select the dictionary you want to install from the list.
 +
 +
Alternatively, you can install the {{Pkg|hunspell}} package. You also need to install dictionaries for your language, such as {{Pkg|hunspell-fr}} (for the French language) or {{Pkg|hunspell-he}} (for Hebrew).
  
Visit https://addons.mozilla.org/en-US/firefox/browse/type:4/ and install.
+
By default, Firefox will try to symlink all your hunspell dictionaries in {{ic|/usr/lib/firefox/dictionaries}}. If you want to have less dictionaries offered to you in Firefox, you can remove some of those links. Be aware that it may not stand an upgrade of Firefox.
  
If you want to custom one, take a look at: {{ic|~/.mozilla/firefox/xxx.default/searchplugins/}} where xxx is your profile ID).
+
When your default language choice does not stick, see [[#Firefox does not remember default spell check language]].
  
Yet another repository of premade searchbar engines: [http://mycroft.mozdev.org/ http://mycroft.mozdev.org/]
+
=== Adding search engines ===
  
Also, you can use [https://firefox.maltekraus.de/extensions/add-to-search-bar add-to-searchbar] extension to add a search to your search bar from any web site, like Opera browser.
+
Search engines can be added to Firefox through normal add-ons, see [https://addons.mozilla.org/firefox/search-tools/ this page] for a list of available search engines.
  
====arch-firefox-search====
+
A very extensive list of search engines can be found [http://mycroft.mozdev.org/ here].
Adds Arch-specific searches (AUR, wiki, forum, etc, as specified by user) to the Firefox search toolbar.
+
# pacman -S arch-firefox-search
+
  
== Projects related to Firefox ==
+
Also, you can use the [https://firefox.maltekraus.de/extensions/add-to-search-bar add-to-searchbar] extension to add a search to your search bar from any web site, by simply right clicking on the site's search field and selecting ''Add to Search Bar...''
=== Firefox derivatives ===
+
Two different forks of Mozilla Firefox:
+
  
*Debian’s Iceweasel ([[Wikipedia:Iceweasel]]; http://wiki.debian.org/Iceweasel). It is being developed by Debian and is based on 2.0.
+
==== arch-firefox-search ====
*GNU/IceCat ([[Wikipedia:GNU IceCat]]; AUR: {{AUR|icecat}}) - formerly known as GNU IceWeasel, is a web browser distributed by the GNU Project. IceCat is made entirely of free software. It is compatible with the GNU/Linux operating system and almost all of Firefox's addons. GNU/IceCat really can fully replace Firefox.
+
  
=== Firefox with better KDE integration ===
+
Install the {{Pkg|arch-firefox-search}} package to add Arch-specific searches (AUR, wiki, forum, etc, as specified by user) to the Firefox search toolbar.
*{{AUR|firefox-kde-opensuse}}
+
:with OpenSUSE patch, integrates better with KDE.  OpenSUSE's patch and integration of Firefox with KDE is considered the best by many users.
+
  
*{{Pkg|kpartsplugin}}
+
=== Multimedia playback ===
:This plugin uses KDE's KParts to embed file viewers into non-KDE browsers
+
  
*[http://kde-look.org/content/show.php/?content=117962 Oxygen KDE]
+
Firefox will try to use [[FFmpeg]] for playing multimedia inside HTML5 {{ic|<audio>}} and {{ic|<video>}} elements. For this to work, the {{Pkg|ffmpeg}} package needs to be installed.
:This addon provides further integration with KDE's Oxygen theme, color scheme detection, Faenza icons and various customizations.
+
 
 +
Restart Firefox, and go to [https://www.youtube.com/html5 YouTube's HTML5 page], [http://www.quirksmode.org/html5/tests/video.html video-test page] or [http://hpr.dogphilosophy.net/test/ audio-test page] to check which formats are actually supported.
 +
 
 +
See also [[Firefox tweaks#Enable additional media codecs]] for advanced configuration.
 +
 
 +
== Tips and tricks ==
 +
 
 +
=== Screenshot of webpage ===
 +
 
 +
To use Firefox to take a screenshot of a webpage open the developer console using {{ic|Shift+F2}}. Then type in:
 +
 
 +
screenshot ''filename''
 +
 
 +
where ''filename'' is optional.
 +
 
 +
To take a screenshot of the entire page, not just the section displayed on the screen, use the {{ic|--fullpage}} option:
 +
 
 +
screenshot --fullpage ''filename''
  
 
== Troubleshooting ==
 
== Troubleshooting ==
  
=== Firefox 4 New Menu Bar/Firefox Button ===
+
=== Firefox startup takes very long ===
By default, Arch Linux shows the classic layout of the menu bar. To activate the new Firefox 4 layout with the "Firefox" button replacing the menu bar, uncheck View -> Toolbars -> Menubar.
+
  
In GNU/Linux, you will just get a plain grey button instead of the new orange one from Windows. However you can change this to either a Firefox icon or the icon followed by the "Firefox" text.
+
If Firefox takes much longer to start up than other browsers, it may be due to lacking configuration of the localhost in  {{ic|/etc/hosts}}. See [[Network configuration#Local network hostname resolution]] on how to set it up.  
  
Adding the following to your {{ic|~/.mozilla/firefox/userprofile/chrome/userChrome.css}} file will place the icon before the text:
+
=== Font troubleshooting ===
{{bc|#appmenu-toolbar-button {
+
  list-style-image: url("chrome://branding/content/icon16.png");
+
}
+
}}
+
Adding the following to the same file will ''remove'' the "Firefox" text:
+
{{bc|#appmenu-toolbar-button > .toolbarbutton-text,
+
#appmenu-toolbar-button > .toolbarbutton-menu-dropmarker {
+
  display: none !important;
+
}
+
}}
+
  
{{Note|You need to create both the {{ic|chrome}} directory and {{ic|userChrome.css}}, if they do not already exist.}}
+
See [[Font configuration]].
  
=== Open containing folder problems (KDE) ===
+
=== Setting an email client ===
If Firefox launches something other than your preferred file manager when using the "Open Containing Folder" option in the Downloads manager, make sure you select your file manager of choice (e.g. Dolphin) in KDE's System Settings:
+
:'''System Settings -> Default Applications -> File Manager'''
+
  
If you have already selected your file manager of choice and Cervisia (or a file manager other than your favorite) is opening modify your user's {{ic|~/.local/share/applications/defaults.list}} to include these two lines:
+
Inside the browser, {{ic|mailto}} links by default are opened by a web application such as Gmail or Yahoo Mail.  To set an external email program, go to ''Preferences > Applications'' and modify the ''action'' corresponding to the {{ic|mailto}} content type; the file path will need to be designated (e.g. {{ic|/usr/bin/kmail}} for Kmail).
x-directory/normal=kde4-dolphin.desktop;kde4-kfmclient_dir.desktop;
+
 
  inode/directory=kde4-dolphin.desktop;kde4-kfmclient_dir.desktop;kde4-gwenview.desktop;kde4-filelight.desktop;kde4-cervisia.desktop;
+
Outside the browser, {{ic|mailto}} links are handled by the {{ic|x-scheme-handler/mailto}} mime type, which can be easily configured with [[xdg-mime]]. See [[Default applications]] for details and alternatives.
 +
 
 +
=== File association ===
 +
 
 +
See [[Default applications]].
 +
 
 +
==== File association problems ====
 +
 
 +
{{Expansion|Mention {{ic|xdg-open}} trick in {{ic|Preferences > Applications}}, and possible mistakes with {{ic|octet/binary-stream}} [https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/918019/comments/12]}}
 +
 
 +
{{Deletion|1={{Pkg|firefox}} does not use {{Pkg|libgnome}} for version 50 and later. Waiting for Firefox 50 and then remove it. See [https://bugzilla.mozilla.org/show_bug.cgi?id=694570 this bug] for detail.}}
 +
 
 +
For non-[[GNOME]] users, Firefox may not associate file types properly or at all (in the "Open With" part of the download dialog). Installing {{Pkg|libgnome}} amends the problem.
 +
 
 +
See also [http://alien.slackbook.org/blog/make-firefox-understand-downloaded-files/].
  
 
=== Firefox keeps creating ~/Desktop even when this is not desired ===
 
=== Firefox keeps creating ~/Desktop even when this is not desired ===
Firefox uses {{ic|~/Desktop}} as the default place for download and upload files. To set it to another folder, create {{ic|~/.config/user-dirs.dirs}} and add:
 
XDG_DESKTOP_DIR="/home/<user>/"
 
XDG_DOWNLOAD_DIR="/home/<user>/<dir>"
 
XDG_TEMPLATES_DIR="/home/<user>/<dir>"
 
XDG_PUBLICSHARE_DIR="/home/<user>/<dir>"
 
XDG_DOCUMENTS_DIR="/home/<user>/<dir>"
 
XDG_MUSIC_DIR="/home/<user>/<dir>"
 
XDG_PICTURES_DIR="/home/<user>/<dir>"
 
XDG_VIDEOS_DIR="/home/<user>/<dir>"
 
Change {{ic|<user>}} and {{ic|<dir>}} to the actual directory.
 
  
=== How to prevent plugins from allowing popups? ===
+
Firefox uses {{ic|~/Desktop}} as the default place for download and upload files. To change it to another folder, set the {{ic|XDG_DESKTOP_DIR}} option as explained in [[XDG user directories]].
Ever wondered why pop-ups appear even though you have blocked them? It seems that the Flash plugin can bypass default settings and annoy us with those pesky pop-ups. Fear not, for we can prevent it from doing that.
+
 
 +
=== Make plugins respect blocked pop-ups ===
 +
 
 +
Some plugins can misbehave and bypass the default settings, such as the Flash plugin. You can prevent this by doing the following:
  
To get around it:
+
# Type {{ic|about:config}} into the address bar.
# Type about:config into the Firefox location bar.
+
# Right-click on the page and select {{ic|New}} and then {{ic|Integer}}.
# Right-click on the page and select New and then Integer.
+
# Name it {{ic|privacy.popups.disable_from_plugins}}.
# Name it privacy.popups.disable_from_plugins
+
 
# Set the value to 2.
 
# Set the value to 2.
  
 
The possible values are:
 
The possible values are:
* 0: Allow all popups from plugins.
+
* '''0''': Allow all popups from plugins.
* 1: Allow popups, but limit them to dom.popup_maximum.
+
* '''1''': Allow popups, but limit them to dom.popup_maximum.
* 2: Block popups from plugins.
+
* '''2''': Block popups from plugins.
* 3: Block popups from plugins, even on whitelisted sites.
+
* '''3''': Block popups from plugins, even on whitelisted sites.
  
 
=== Middle-click errors ===
 
=== Middle-click errors ===
  ! The URL is not valid and cannot be loaded.
+
 
 +
A common error message you can get while using the middle mouse button in Firefox is:
 +
  The URL is not valid and cannot be loaded.
 +
 
 
Another symptom is that middle-clicking results in unexpected behavior, like accessing a random web page.
 
Another symptom is that middle-clicking results in unexpected behavior, like accessing a random web page.
  
The reason stems from the use of the middle mouse buttons in UNIX-like operating systems. The middle mouse button is used to paste whatever text has been highlighted/added to the clipboard. Then there is the possibly conflicting feature in Firefox, which defaults to loading the URL of the corresponding text when the button is depressed. This can be disabled like so:
+
The reason stems from the use of the middle mouse buttons in UNIX-like operating systems. The middle mouse button is used to paste whatever text has been highlighted/added to the clipboard. Then there is the possibly conflicting feature in Firefox, which defaults to loading the URL of the corresponding text when the button is depressed. This can be easily disabled by going to {{ic|about:config}} and setting the {{ic|middlemouse.contentLoadURL}} option to '''false'''.
  
Open the browser, and type the following into the address bar:
+
Alternatively, having the traditional scroll cursor on middle-click (default behavior on Windows browsers) can be achieved by searching for {{ic|general.autoScroll}} and setting it to '''true'''.
about:config
+
Search for '''middlemouse.contentLoadURL''' and set it to false.
+
 
+
Alternatively, having the traditional scroll cursor on middle-click (default behaviour on Windows browsers) can be achieved by searching for '''general.autoScroll''' and setting it to true.
+
  
 
=== Backspace does not work as the 'Back' button ===
 
=== Backspace does not work as the 'Back' button ===
As per [http://ubuntu.wordpress.com/2006/12/21/fix-firefox-backspace-to-take-you-to-the-previous-page/ this article], the feature has been removed in order to fix a bug. Follow the next steps to retain the original behaviour.
 
  
Open the browser and type the following address:
+
As per [http://ubuntu.wordpress.com/2006/12/21/fix-firefox-backspace-to-take-you-to-the-previous-page/ this article], the feature has been removed in order to fix a bug. To re-introduce the original behavior go to {{ic|about:config}} and set the {{ic|browser.backspace_action}} option to '''0''' (zero).
about:config
+
Search for '''browser.backspace_action''' and set it to 0 (zero).
+
  
=== Firefox does not remember login information ===
+
=== Firefox does not remember login information ===
It may be due to a corrupted {{ic|cookies.sqlite}} file in [http://support.mozilla.com/en-US/kb/Profiles#How_to_find_your_profile Firefox's profile] folder. In order to fix this, just rename or remove the cookie.sqlite while Firefox is not running.
+
 
 +
It may be due to a corrupted {{ic|cookies.sqlite}} file in [http://support.mozilla.com/en-US/kb/Profiles#How_to_find_your_profile Firefox's profile] folder. In order to fix this, just rename or remove {{ic|cookie.sqlite}} while Firefox is not running.
  
 
Open a terminal of choice and type the following:
 
Open a terminal of choice and type the following:
Line 166: Line 214:
 
Restart Firefox and see if it solved the problem.
 
Restart Firefox and see if it solved the problem.
  
=== Broken websites / input fields with dark Gtk Themes ===
+
=== Unreadable input fields with dark GTK+ themes ===
When using a dark [[GTK]] theme, one might encounter Internet pages with unreadable input and text fields (p.e. Amazon - white text on white background). This can happen because the site only sets either background or text color, and Firefox takes the other one from the theme.
+
  
A work around is to explicitly setting standard colours for all web pages in {{ic|~/.mozilla/firefox/.../chrome/userContent.css}}.
+
{{Merge|Firefox tweaks#Appearance|Anything on that page might be in troubleshooting section as well, so let us keep the info in one place.}}
 +
 
 +
When using a dark [[GTK+]] theme, one might encounter Internet pages with unreadable input and text fields (e.g. Amazon can have white text on white background). This can happen because the site only sets either background or text color, and Firefox takes the other one from the theme.
 +
 
 +
A work around is to explicitly setting standard colors for all web pages in {{ic|~/.mozilla/firefox/xxxxxxxx.default/chrome/userContent.css}} or using [https://addons.mozilla.org/firefox/addon/stylish/ stylish add-on].
  
 
The following sets input fields to standard black text / white background; both can be overridden by the displayed site, so that colors are seen as intended:
 
The following sets input fields to standard black text / white background; both can be overridden by the displayed site, so that colors are seen as intended:
 +
 +
{{Note|If you want {{ic|urlbar}} and {{ic|searchbar}} to be {{ic|white}} remove the two first {{ic|:not}} css selectors.}}
 
{{bc|
 
{{bc|
input {
+
1=input:not(.urlbar-input):not(.textbox-input):not(.form-control):not([type='checkbox']) {
 
     -moz-appearance: none !important;
 
     -moz-appearance: none !important;
 
     background-color: white;
 
     background-color: white;
 
     color: black;
 
     color: black;
 +
}
 +
 +
#downloads-indicator-counter {
 +
    color: white;
 
}
 
}
  
Line 183: Line 240:
 
     background-color: white;
 
     background-color: white;
 
     color: black;
 
     color: black;
}
 
}}
 
This will force the colours ("Allow pages to choose their own colors [..]" setting, in the '''Preferences > Content > Color''' dialog):
 
{{bc|
 
input {
 
    -moz-appearance: none !important;
 
    background-color: pink !important;
 
    color: green !important;
 
 
}
 
}
  
textarea {
+
select {
 
     -moz-appearance: none !important;
 
     -moz-appearance: none !important;
     background-color: pink !important;
+
     background-color: white;
     color: green !important;
+
     color: black;
 
}
 
}
 
}}
 
}}
Change color values to suit, or use an add-on like [https://addons.mozilla.org/en-US/firefox/addon/2108 Stylish].
 
  
=== File association problems ===
+
Another workaround is to force Firefox to use a light theme (e.g. "Adwaita:light"):
For non-[[GNOME]] users, Firefox may not associate file types (in the "Open With" part of the download dialog). Installing {{Pkg|libgnome}} amends the problem:
+
pacman -S libgnome
+
If you are using KDE you can also do the following:
+
ln -s ~/.local/share/applications/mimeapps.list ~/.local/share/applications/mimeinfo.cache
+
From now on Firefox should use the applications which are explicitly set in KDE.
+
  
=== "I'm Feeling Lucky" Mode ===
+
# Copy {{ic|/usr/share/applications/firefox.desktop}} to {{ic|~/.local/share/applications/firefox.desktop}} and replace all occurrences of {{ic|1=Exec=firefox}} with {{ic|1=Exec=env GTK_THEME=Adwaita:light firefox}}.
Some search engines have a feeling lucky feature. For example Google has "I'm Feeling Lucky"  and DuckDuckGo has "I'm Feeling Ducky".
+
# Close all running instances of Firefox and restart your window manager/desktop environment.
  
To activate them:
+
=== "Do you want Firefox to save your tabs for the next time it starts?" dialog does not appear ===
# Type "'''about:config'''" in the address bar.
+
# Search for the string '''keyword.url'''
+
# Modify its value (if any) to the URL of the search engine.
+
  
:: For google, set it to:
+
From the [http://support.mozilla.com/en-US/questions/767751 Mozilla support] site:
:: {{bc|<nowiki>http://www.google.com/search?btnI=I%27m+Feeling+Lucky&q=</nowiki>}}
+
:: For DuckDuckGo, set it to:
+
:: {{bc|<nowiki>https://duckduckgo.com/?q=\</nowiki>}}
+
  
=== "Do you want Firefox to save your tabs for the next time it starts?" dialog does not appear ===
+
# Type {{ic|about:config}} in the address bar.
From the [http://support.mozilla.com/en-US/questions/767751 Mozilla Support] site:
+
# Set {{ic|browser.warnOnQuit}} to '''true'''.
 +
# Set {{ic|browser.showQuitWarning}} to '''true'''.
 +
 
 +
=== Silently fails when installing desktop apps from marketplace ===
 +
 
 +
Installation of apps from firefox os marketplace will silently fail if there is no {{ic|~/.local/share/applications}} folder.
 +
 
 +
=== Firefox detects the wrong version of my plugin ===
 +
 
 +
When you close Firefox, the latter saves the current timestamp and version of your plugins inside {{ic|pluginreg.dat}} located in your profile folder, typically in {{ic|~/.mozilla/firefox/''some name''.default/}}.
 +
 
 +
If you upgraded your plugin when Firefox was still running, you will thus have the wrong information inside that file. The next time you will restart Firefox you will get that message {{ic|Firefox has prevented the outdated plugin "XXXX" from running on ...}} when you will be trying to open content dedicated to that plugin on the web. This problem often appears with the official [[Browser plugins#Flash Player|Adobe Flash Player plugin]] which has been upgraded while Firefox was still running.
 +
 
 +
The solution is to remove the file {{ic|pluginreg.dat}} from your profile and that is it. Firefox will not complain about the missing file as it will be recreated the next time Firefox will be closed.
 +
[https://bugzilla.mozilla.org/show_bug.cgi?id=1109795#c16]
 +
 
 +
=== Javascript context menu does not appear on some sites ===
 +
 
 +
In {{ic|about:config}}, unset the {{ic|dom.w3c_touch_events.enabled}} setting.
  
# Type "'''about:config'''" in the address bar.
+
=== Firefox does not remember default spell check language ===
# Set '''browser.warnOnQuit''' to '''true'''.
+
# Set '''browser.showQuitWarning''' to '''true'''.
+
  
=== Firefox has high CPU usage and feels slow on scrolling with nVidia GPUs ===
+
The default spell checking language can be set as follows:
  
In some cases, forcing the proprietary nVidia driver to store pixmaps in video memory instead of system memory can yield massive improvements in the perceived performance of pixmap-intensive applications like Firefox. Run
+
# Type {{ic|about:config}} in the address bar.
 +
# Set {{ic|spellchecker.dictionary}} to your language of choice, for instance {{ic|en_GB}}.
 +
# Notice that the for dictionaries installed as a Firefox plugin the notation is {{ic|en-GB}}, and for {{Pkg|hunspell}} dictionaries the notation is {{ic|en_GB}}.
  
$ nvidia-settings -a InitialPixmapPlacement=2
+
When you only have system wide dictionaries installed with {{Pkg|hunspell}}, Firefox might not remember your default dictionary language settings. This can be fixed by having at least one [https://addons.mozilla.org/firefox/language-tools/ dictionary] installed as a Firefox plugin. Notice that now you will also have a tab '''Dictionaries''' in '''add-ons'''.
  
from the terminal; if desired results are achieved add this line to a script and use your desktop environment's autorun facilities to execute it on every startup. Alternatively, add the parameter to your {{ic|~/.nvidia-settings-rc}} and run
+
Related questions on the '''StackExchange''' platform: [http://stackoverflow.com/questions/26936792/change-firefox-spell-check-default-language/29446115], [http://stackoverflow.com/questions/21542515/change-default-language-on-firefox/29446353], [http://askubuntu.com/questions/184300/how-can-i-change-firefoxs-default-dictionary/576877]
  
$ nvidia-settings --load-config-only
+
Related bug reports: [https://bugzilla.mozilla.org/show_bug.cgi?id=776028 Bugzilla 776028], [https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1026869 Ubuntu bug 1026869]
  
on startup. This setting is documented in [http://cgit.freedesktop.org/~aplattner/nvidia-settings/tree/src/libXNVCtrl/NVCtrl.h?id=b27db3d10d58b821e87fbe3f46166e02dc589855#n2797 nvidia-settings source code]. Make sure you have added other perfomance-improving settings, see [[NVIDIA]].
+
=== Some MathML symbols are missing ===
  
=== Firefox uses ugly fonts for its interface ===
+
You need some Math fonts, namely Latin Modern Math and STIX (see this MDN page: [https://developer.mozilla.org/en-US/docs/Mozilla/MathML_Project/Fonts#Linux]), to display MathML correctly.
  
If the fonts in the menu bar look ugly to you, chances are you're missing better looking fonts for Firefox to use. As a quick remedy, just install Type 1 fonts:
+
In Arch Linux, these fonts are provided by {{Pkg|texlive-core}} '''and''' {{Pkg|texlive-fontsextra}}, but they are not available to fontconfig by default. See [[TeX Live#Fonts]] for details. You can also try other [[Fonts#Math|Math fonts]].
$ pacman -S xorg-fonts-type1
+
  
=== Firefox uses ugly fonts on certain webpages ===
+
=== Picture flickers while scrolling ===
 +
{{Note|Problem available in some MATE desktops}}
 +
Uncheck the "smooth scrolling" settings:
 +
Edit > Settings > Advanced > General > Use smooth scrolling
  
When Firefox uses bitmap fonts, it can happen that on certain webpages the fonts are very ugly (compared to Google Chrome for example):
+
=== Tearing video in fullscreen mode ===
  
http://i.imgur.com/SMVdi.png vs http://i.imgur.com/jNmxU.png
+
If you are using the Xorg Intel or Nouveau drivers and experience tearing video in fullscreen mode, try [[Firefox tweaks#Enable OpenGL Off-Main-Thread Compositing (OMTC)]].
  
To fix that, just disable bitmap fonts for X:
+
=== Firefox looks bad with GTK+ >=3.20 ===
$ sudo ln -s /etc/fonts/conf.avail/70-no-bitmaps.conf /etc/fonts/conf.d/
+
  
=== The menu can't pop up after updating to Firefox 13 ===
+
Firefox (as of version 47) [https://bugzilla.mozilla.org/show_bug.cgi?id=1264079 does not support] GTK+ >=3.20 and may look unsightly as a result. A possible resolution is compiling Firefox against GTK2 instead, see {{AUR|firefox-gtk2}}. Alternatively, you may use [[Unofficial_user_repositories#markzz|markzz's repository]] for pre-built GTK2 Firefox packages.
  
This problem may happen to some Chinese user who use {{pkg|fcitx}} as an input method. The problem may be caused by false environment variables of fcitx, please check it.
+
== See also ==
Or you may solve it by installing {{pkg|fcitx-gtk2}}, {{pkg|fcitx-gtk3}}, and {{pkg|fcitx-qt}}.
+
  
==See also==
+
* [http://www.mozilla.org/firefox/ Official website]
* [http://web.glandium.org/blog/?p=97 Facts about Debian and Mozilla® Firefox]
+
* [http://www.mozilla.org/ Mozilla Foundation]
:An account of the trademark issues from the Firefox package maintainer for Debian.
+
* [https://wiki.mozilla.org/Firefox Firefox wiki]
* [http://www.gnu.org/software/gnuzilla/ Gnuzilla and IceWeasel]
+
* [https://addons.mozilla.org/ Firefox Add-ons]
:Official website for the GNU Mozilla forks.
+
* [https://addons.mozilla.org/firefox/themes/ Firefox themes]

Latest revision as of 03:15, 3 August 2016

Firefox is a popular open-source graphical web browser from Mozilla.

Installing

Firefox can be installed with the firefox package.

Other alternatives include:

  • Firefox Extended Support Release — long-term supported version
https://www.mozilla.org/firefox/organizations/ || firefox-esrAUR or firefox-esr-binAUR
  • Firefox Beta — cutting-edge version
https://www.mozilla.org/firefox/channel/#beta || firefox-betaAUR or firefox-beta-binAUR
  • Firefox Developer Edition/Aurora — for developers
https://www.mozilla.org/firefox/channel/#developer || firefox-auroraAUR
  • Firefox Nightly — nightly builds for testing
https://nightly.mozilla.org/ || firefox-nightlyAUR
  • Firefox KDE — Version of Firefox that incorporates an OpenSUSE patch for better KDE integration than is possible through simple Firefox plugins.
https://build.opensuse.org/package/show/mozilla:Factory/MozillaFirefox || firefox-kde-opensuseAUR

Here you can find an overview of Mozilla's releases.

There are a number of language packs available for Firefox, other than the standard English. Language packs are usually named as firefox-i18n-languagecode (where languagecode can be any language code, such as de, ja, fr, etc.). For a list of available language packs see this.

Add-ons

Firefox is well known for its large library of add-ons which can be used to add new features or modify the behavior of existing features of Firefox. You can find new add-ons or manage installed add-ons with Firefox's "Add-ons Manager."

For a list of popular add-ons, see Mozilla's add-on list sorted by popularity. See also List of Firefox extensions on Wikipedia.

Configuration

Firefox exposes a number of configuration options. To examine them, enter:

about:config

in the Firefox address bar.

Once set, these affect the user's current profile, and may be synchronized across all devices via Firefox Sync. Please note that only a subset of the about:config entries are synchronized by this method, and the exact subset may be found by searching for services.sync.prefs in about:config. Additional preferences and 3rd party preferences may be synchronized by creating new boolean entries prepending the config value with services.sync.prefs.sync (documentation is still applicable.) To synchronize the whitelist for the extension NoScript:

services.sync.prefs.sync.capability.policy.maonoscript.sites

The boolean noscript.sync.enabled must be set to true to synchronize the remainder of NoScript's preferences via Firefox Sync.

Firefox also allows configuration for a profile via a user.js file: user.js kept in the profile folder, usually ~/.mozilla/firefox/some name.default/. For a useful starting point, see e.g custom user.js which is targeted at privacy/security conscious users.

One drawback of the above approach is that it is not applied system-wide. Furthermore, this is not useful as a "pre-configuration", since the profile directory is created after first launch of the browser. You can, however, let firefox create a new profile and, after closing it again, copy the contents of an already created profile folder into it.

Sometimes it may be desired to lock certain settings, a feature useful in widespread deployments of customized Firefox. In order to create a system-wide configuration, follow the steps outlined in Locking preferences:

1. Create /usr/lib/firefox/defaults/pref/local-settings.js:

pref("general.config.obscure_value", 0);
pref("general.config.filename", "mozilla.cfg");

2. Create /usr/lib/firefox/mozilla.cfg (this stores the actual configuration):

//
//...your settings...
// e.g to disable Pocket, uncomment the following line
// lockPref("browser.pocket.enabled", false);

Please note that the first line must contain exactly //. The syntax of the file is similar to that of user.js.

Plugins

See the main article: Browser plugins

To find out what plugins are installed/enabled, enter:

about:plugins

in the Firefox address bar or go to the Add-ons entry in the Firefox Menu and select the Plugins tab.

GNOME Keyring integration

Install mozilla-extension-gnome-keyring-gitAUR (all-JavaScript implementation) to integrate Firefox with GNOME Keyring. To make firefox-gnome-keyring use your login keychain, set extensions.gnome-keyring.keyringName to "login" (without the double quotes) in about:config. Note the lowercase 'l' despite the the keychain name having an uppercase 'L' in Seahorse.

KDE integration

Warning: Since GTK3 was updated to 3.20.x, there are several broken themes. Including Breeze, the recommended theme for integration between KDE and GTK styles. Some of the issues are invisible scroll bars, no text highlight on selection, invisible checkboxes, among others. As a workaround while the themes are upgraded you can do the following after installing kde-gtk-config, go to System Settings -> Application Style -> GNOME Application Style (GTK) and choose in the Select a GTK3 Theme dropdown choose the Default theme, also make sure Show icons in GTK buttons and Show icons in GTK are checked. For further information on the compatibility issue above visit the GTK3 3.20 upgrade thread in the Arch Forums.
  • To bring the KDE look to GTK apps (including Firefox), install breeze-gtk and kde-gtk-config. Afterwards, go to System Settings -> Application Style -> GTK. Be sure to choose 'Breeze' in 'Select a GTK2/GTK3 Theme' and check 'Show icons in GTK buttons' and 'Show icons in GTK'.
  • To use KDE's KPart technology with Firefox, by embedding different KDE file viewers into the browser, you can install kpartsplugin.
  • For integration with KDE’s mime type system and file dialogs, one can use firefox-kde-opensuseAUR variant from AUR with OpenSUSE’s patches applied.

Dictionaries for spell checking

To enable spell checking for a specific language right click on any text field and check the Check Spelling box. To select a language for spell checking to you have right click again and select your language from the Languages sub-menu.

To get more languages just click Add Dictionaries... and select the dictionary you want to install from the list.

Alternatively, you can install the hunspell package. You also need to install dictionaries for your language, such as hunspell-fr (for the French language) or hunspell-he (for Hebrew).

By default, Firefox will try to symlink all your hunspell dictionaries in /usr/lib/firefox/dictionaries. If you want to have less dictionaries offered to you in Firefox, you can remove some of those links. Be aware that it may not stand an upgrade of Firefox.

When your default language choice does not stick, see #Firefox does not remember default spell check language.

Adding search engines

Search engines can be added to Firefox through normal add-ons, see this page for a list of available search engines.

A very extensive list of search engines can be found here.

Also, you can use the add-to-searchbar extension to add a search to your search bar from any web site, by simply right clicking on the site's search field and selecting Add to Search Bar...

arch-firefox-search

Install the arch-firefox-search package to add Arch-specific searches (AUR, wiki, forum, etc, as specified by user) to the Firefox search toolbar.

Multimedia playback

Firefox will try to use FFmpeg for playing multimedia inside HTML5 <audio> and <video> elements. For this to work, the ffmpeg package needs to be installed.

Restart Firefox, and go to YouTube's HTML5 page, video-test page or audio-test page to check which formats are actually supported.

See also Firefox tweaks#Enable additional media codecs for advanced configuration.

Tips and tricks

Screenshot of webpage

To use Firefox to take a screenshot of a webpage open the developer console using Shift+F2. Then type in:

screenshot filename

where filename is optional.

To take a screenshot of the entire page, not just the section displayed on the screen, use the --fullpage option:

screenshot --fullpage filename

Troubleshooting

Firefox startup takes very long

If Firefox takes much longer to start up than other browsers, it may be due to lacking configuration of the localhost in /etc/hosts. See Network configuration#Local network hostname resolution on how to set it up.

Font troubleshooting

See Font configuration.

Setting an email client

Inside the browser, mailto links by default are opened by a web application such as Gmail or Yahoo Mail. To set an external email program, go to Preferences > Applications and modify the action corresponding to the mailto content type; the file path will need to be designated (e.g. /usr/bin/kmail for Kmail).

Outside the browser, mailto links are handled by the x-scheme-handler/mailto mime type, which can be easily configured with xdg-mime. See Default applications for details and alternatives.

File association

See Default applications.

File association problems

Tango-view-fullscreen.pngThis article or section needs expansion.Tango-view-fullscreen.png

Reason: Mention xdg-open trick in Preferences > Applications, and possible mistakes with octet/binary-stream [1] (Discuss in Talk:Firefox#)

Tango-edit-cut.pngThis section is being considered for removal.Tango-edit-cut.png

Reason: firefox does not use libgnome for version 50 and later. Waiting for Firefox 50 and then remove it. See this bug for detail. (Discuss in Talk:Firefox#)

For non-GNOME users, Firefox may not associate file types properly or at all (in the "Open With" part of the download dialog). Installing libgnome amends the problem.

See also [2].

Firefox keeps creating ~/Desktop even when this is not desired

Firefox uses ~/Desktop as the default place for download and upload files. To change it to another folder, set the XDG_DESKTOP_DIR option as explained in XDG user directories.

Make plugins respect blocked pop-ups

Some plugins can misbehave and bypass the default settings, such as the Flash plugin. You can prevent this by doing the following:

  1. Type about:config into the address bar.
  2. Right-click on the page and select New and then Integer.
  3. Name it privacy.popups.disable_from_plugins.
  4. Set the value to 2.

The possible values are:

  • 0: Allow all popups from plugins.
  • 1: Allow popups, but limit them to dom.popup_maximum.
  • 2: Block popups from plugins.
  • 3: Block popups from plugins, even on whitelisted sites.

Middle-click errors

A common error message you can get while using the middle mouse button in Firefox is:

The URL is not valid and cannot be loaded.

Another symptom is that middle-clicking results in unexpected behavior, like accessing a random web page.

The reason stems from the use of the middle mouse buttons in UNIX-like operating systems. The middle mouse button is used to paste whatever text has been highlighted/added to the clipboard. Then there is the possibly conflicting feature in Firefox, which defaults to loading the URL of the corresponding text when the button is depressed. This can be easily disabled by going to about:config and setting the middlemouse.contentLoadURL option to false.

Alternatively, having the traditional scroll cursor on middle-click (default behavior on Windows browsers) can be achieved by searching for general.autoScroll and setting it to true.

Backspace does not work as the 'Back' button

As per this article, the feature has been removed in order to fix a bug. To re-introduce the original behavior go to about:config and set the browser.backspace_action option to 0 (zero).

Firefox does not remember login information

It may be due to a corrupted cookies.sqlite file in Firefox's profile folder. In order to fix this, just rename or remove cookie.sqlite while Firefox is not running.

Open a terminal of choice and type the following:

$ cd ~/.mozilla/firefox/xxxxxxxx.default/
$ rm -f cookies.sqlite
Note: xxxxxxxx represents a random string of 8 characters.

Restart Firefox and see if it solved the problem.

Unreadable input fields with dark GTK+ themes

Merge-arrows-2.pngThis article or section is a candidate for merging with Firefox tweaks#Appearance.Merge-arrows-2.png

Notes: Anything on that page might be in troubleshooting section as well, so let us keep the info in one place. (Discuss in Talk:Firefox#)

When using a dark GTK+ theme, one might encounter Internet pages with unreadable input and text fields (e.g. Amazon can have white text on white background). This can happen because the site only sets either background or text color, and Firefox takes the other one from the theme.

A work around is to explicitly setting standard colors for all web pages in ~/.mozilla/firefox/xxxxxxxx.default/chrome/userContent.css or using stylish add-on.

The following sets input fields to standard black text / white background; both can be overridden by the displayed site, so that colors are seen as intended:

Note: If you want urlbar and searchbar to be white remove the two first :not css selectors.
input:not(.urlbar-input):not(.textbox-input):not(.form-control):not([type='checkbox']) {
    -moz-appearance: none !important;
    background-color: white;
    color: black;
}

#downloads-indicator-counter {
    color: white;
}

textarea {
    -moz-appearance: none !important;
    background-color: white;
    color: black;
}

select {
    -moz-appearance: none !important;
    background-color: white;
    color: black;
}

Another workaround is to force Firefox to use a light theme (e.g. "Adwaita:light"):

  1. Copy /usr/share/applications/firefox.desktop to ~/.local/share/applications/firefox.desktop and replace all occurrences of Exec=firefox with Exec=env GTK_THEME=Adwaita:light firefox.
  2. Close all running instances of Firefox and restart your window manager/desktop environment.

"Do you want Firefox to save your tabs for the next time it starts?" dialog does not appear

From the Mozilla support site:

  1. Type about:config in the address bar.
  2. Set browser.warnOnQuit to true.
  3. Set browser.showQuitWarning to true.

Silently fails when installing desktop apps from marketplace

Installation of apps from firefox os marketplace will silently fail if there is no ~/.local/share/applications folder.

Firefox detects the wrong version of my plugin

When you close Firefox, the latter saves the current timestamp and version of your plugins inside pluginreg.dat located in your profile folder, typically in ~/.mozilla/firefox/some name.default/.

If you upgraded your plugin when Firefox was still running, you will thus have the wrong information inside that file. The next time you will restart Firefox you will get that message Firefox has prevented the outdated plugin "XXXX" from running on ... when you will be trying to open content dedicated to that plugin on the web. This problem often appears with the official Adobe Flash Player plugin which has been upgraded while Firefox was still running.

The solution is to remove the file pluginreg.dat from your profile and that is it. Firefox will not complain about the missing file as it will be recreated the next time Firefox will be closed. [3]

Javascript context menu does not appear on some sites

In about:config, unset the dom.w3c_touch_events.enabled setting.

Firefox does not remember default spell check language

The default spell checking language can be set as follows:

  1. Type about:config in the address bar.
  2. Set spellchecker.dictionary to your language of choice, for instance en_GB.
  3. Notice that the for dictionaries installed as a Firefox plugin the notation is en-GB, and for hunspell dictionaries the notation is en_GB.

When you only have system wide dictionaries installed with hunspell, Firefox might not remember your default dictionary language settings. This can be fixed by having at least one dictionary installed as a Firefox plugin. Notice that now you will also have a tab Dictionaries in add-ons.

Related questions on the StackExchange platform: [4], [5], [6]

Related bug reports: Bugzilla 776028, Ubuntu bug 1026869

Some MathML symbols are missing

You need some Math fonts, namely Latin Modern Math and STIX (see this MDN page: [7]), to display MathML correctly.

In Arch Linux, these fonts are provided by texlive-core and texlive-fontsextra, but they are not available to fontconfig by default. See TeX Live#Fonts for details. You can also try other Math fonts.

Picture flickers while scrolling

Note: Problem available in some MATE desktops

Uncheck the "smooth scrolling" settings:

Edit > Settings > Advanced > General > Use smooth scrolling

Tearing video in fullscreen mode

If you are using the Xorg Intel or Nouveau drivers and experience tearing video in fullscreen mode, try Firefox tweaks#Enable OpenGL Off-Main-Thread Compositing (OMTC).

Firefox looks bad with GTK+ >=3.20

Firefox (as of version 47) does not support GTK+ >=3.20 and may look unsightly as a result. A possible resolution is compiling Firefox against GTK2 instead, see firefox-gtk2AUR. Alternatively, you may use markzz's repository for pre-built GTK2 Firefox packages.

See also