I have a dark GTK theme installed in my Ubuntu 10.10 install and a persona installed for Firefox that I also like.

The problem is that Firefox is using my dark GTK theme for items like buttons and text fields on common web pages, and this commonly creates unreadable menus, text areas, and buttons. (white text on white backgrounds, or black text on black buttons).

I don't want to change either theme, because they look great in every other application, and I don't want to have to do something crazy to my Firefox install like use custom user scripts or CSS overrides.

All I want to do is tell Firefox to stop using my GTK theme completely. This appears to be what Google's Chrome browser does and it makes the most sense by far.

How can web developers possibly work around all the possible GTK themes out there?

  • I wonder if anyone has a permanent solution for this so I can just launch firefox from my Gnome 3 activities tab/window... – MarioDS Dec 16 '12 at 14:42
  • @MDeSchaepmeester: See the answer I added here for KDE, maybe it works for Gnome as well: askubuntu.com/a/358493/154613 – Igor Rodriguez Oct 13 '13 at 10:56
  • There are further solutions, including the one that worked for me, on the related question askubuntu.com/q/227727/23786. – CodeMouse92 Mar 14 '16 at 22:33

11 Answers 11


Start Firefox with one of the following command:

  • GTK3 Firefox 46+: env GTK_THEME=Adwaita:light firefox
  • GTK2 Firefox <46: env GTK2_RC_FILES=/usr/share/themes/Simple/gtk-2.0/gtkrc firefox

This will launch Firefox using the Simple/Adwaita:light theme, which is pretty basic and should blend with your Persona. You can try other themes, by replacing Simple with the theme name, but this doesn't work with all themes.

So far I have successfully tested with Simple and Redmond themes...





  • this worked for mw with the 'new wave' and 'redmond' themes only, but it still worked, so I'm very greatful. screenshots are always appreciated, too :) – tamale Oct 21 '10 at 13:56
  • this is awesome!!! – RolandiXor Jan 16 '11 at 21:32
  • which you need to do after quitting your current firefox instance, of course, or the "firefox" script will just instruct the current process to open a new window (and the GTK2_RC_FILES setting is just ignored altogether). – sylvainulg Jan 27 '12 at 10:13
  • 2
    What is the most recent version of firefox this is known to work with? I'm using Firefox 31 on Ubuntu Utopic and, I swear this worked for me once, but I must be hallucinating because it is no longer working no matter what I try. – robru Jul 17 '14 at 23:01
  • 4
    This no longer works with Firefox 46 because of the switch to GTK 3. – Konstantin Pereiaslov May 1 '16 at 13:47

Permanent solution:

You can specify a light GTK theme to use for rendering webpages in about:config. This is great because your system theme will still apply for menus etc. but the webpages will be rendered as they are with light themes.

  1. Navigate to about:config in your Firefox browser
  2. Right click and select new->string
  3. Enter widget.content.gtk-theme-override as the name
  4. Enter a light GTK theme that you have installed on your system for the value. e.g. Arc
  5. Restart firefox.

Source: https://www.reddit.com/r/firefox/comments/6rbvvw/photon_rectangular_tabs_have_landed_in_nightly/dl4318f/

See also https://bugzilla.mozilla.org/show_bug.cgi?id=1283086

  • 2
    I love this and it works. Save the setting in Firefox itself, not somewhere obscure in the system or a desktop entry :) – jocull Nov 6 '18 at 18:43
  • And it's not needed to restart Firefox. It is applied instantly. – Masood Khaari Feb 15 '19 at 14:20
  • 1
    This would have been a nice option except that it does not work anymore. What a shame! Running Firefox nightly 69.0a1 – smac89 May 26 '19 at 7:02
  • Still working for me on the stable version. When 69.0 comes around I'll re-evaluate. – rviertel Jun 3 '19 at 20:19
  • A year later (2020), and we are now on firefox 82. I am glad to say that this still works. Sorry for my initial comment. I set widget.content.gtk-theme-override to High Contrast theme and I have never been happier. Firefox now looks beautiful. The theme only affected input fields, so all of them look very good and I am loving it. I'm now running arch, so in order to get the High Contrast theme, I had to install this package. I'm not sure what to install on Ubuntu, but just wanted to let you guys know what worked – smac89 Sep 6 '20 at 15:58

I would like to add to the great answer of @lovinglinux a way to make Firefox to load the theme when opened from a launcher in the taskbar instead of command line:

  1. Edit /usr/share/applications/firefox.desktop as sudo,
  2. In the "Exec" line, replace the value after the "=" with a command using the instructions provided by the mentioned @lovinglinux:

    bash -c 'GTK2_RC_FILES=/usr/share/themes/Redmond/gtk-2.0/gtkrc firefox %u' Kate editing firefox.desktop

And the result is this:

Firefox with Redmond theme and all other applications with a dark theme

  • 1
    Thank you for showing how to modify the .desktop file. That makes it very convenient! I'm using your solution for LibreOffice. – user25656 Dec 30 '13 at 7:11
  • The desktop file gets overwritten each time that Firefox updates so this is not a permanent solution – rviertel Sep 9 '18 at 16:09

UPDATE: My original answer actually gets overwritten when Firefox updates.

My current (permanent) solution

(where abcdef is a random string)


input:not(.urlbar-input):not(.textbox-input):not(.form-control):not([type='checkbox']):not([type='radio']), textarea, select {
    -moz-appearance: none !important;
    background-color: #eee;
    color: #111;

Original answer

I found a solution to make Firefox completely ignore your GTK theme.

Edit /usr/share/applications/firefox.desktop and change

Exec=firefox %u


Exec=bash -c 'GTK_THEME=" " firefox %u'

When you (re)start FF it will only use the FF theme.

  • 1
    It works. Btw I use Exec=bash -c 'GTK_THEME=Arc-Darker firefox %u'. – mja Apr 4 '18 at 13:15
  • This doesn't work long term because the .desktop file is overwritten when firefox updates – rviertel May 16 '18 at 20:25
  • @rviertel you're right, it does get overwritten. I've updated my answer with my current solution to this problem. – barro32 Jun 12 '18 at 15:30

The best solution to tell Firefox that it should use the light theme instead of the dark is by specifying the GTK_THEME variable prior to launching.

So, 4 ways you get for doing this..

1- from terminal you can do:

GTK_THEME=Adwaita:light firefox

2- if you hate the terminal and wanna close it once firefox works:

GTK_THEME=Adwaita:light firefox &

3- from firefox about:config you can set the following setting to false:


WON'T WORK FOR localhost SITES! so if you are a web developer/designer it won't work out that well for you.

4- if you want this to be the defualt behavior:

Just add two lines to the Firefox launcher script located at /usr/lib/firefox/firefox.sh

in the terminal type down:

sudo gedit /usr/lib/firefox/firefox.sh

look at the beginning of the script for this:



and change it to this:


export GTK_THEME

Finally, restart Firefox.

Hope this helps.

Please help me by voting this up.

Thank you :)

  • This worked for me. Thank you! +1 – VenoM Jun 1 '18 at 3:32

This add-on (suggested by koushik) works well for me.

I'm using Firefox 57 on Ubuntu MATE 17.10

  • Thanks, this extension worked perfectly for Firefox Quantum on Fedora.:) – john400 Aug 29 '18 at 4:35

There is a very simple way to get the default color scheme back for web pages while still keeping your GTK theme for Firefox elements. I know it's not exactly what was asked, but it may help people coming here from a Google search.

  1. Navigate to about:config in your address bar.
  2. Scroll down until you see the settings
    • browser.display.foreground_color
    • browser.diaplay.background_color
  3. If those settings have been modified, right-click them and select reset.

That should be it, no restart necessary. This works with Firefox Quantum.

Settings in about:config


I'm using the Adwaita dark theme with Ubuntu 18. I'm using the default theme in firefox 63.0. The best solution in my case, with no side effects at all, was to force firefox to use a light theme (Adwaita in my case) for web content rendering only :

  • Open about:config in the address bar.
  • Create a new string entry : widget.content.gtk-theme-override ( right click > New > String ).
  • Set the value to the light theme to use for content rendering (Adwaita in my case ).
  • Restart firefox.

Change the GTK theme for content process only


You could start Firefox with a different user and the same profile. Copy your current profile (~/.mozilla/firefox/profile) to that different user's folder, chown it to the user, and then on your console run:

su newuser
firefox -profilemanager

This sounds a bit overkill, but you can put it into a script. Firefox will use the theme on the profile, but keep the unthemed GTK from the new user.

Also, this is the kind of stuff that makes it fun to use Firefox and Ubuntu :P


You can add another theme to Firefox that you like from Tools -> Addons -> Themes. Then just use that theme instead of the default one.

  • 2
    You can't use a different Firefox theme while using Personas – lovinglinux Oct 19 '10 at 20:01
  • 1
    Oh wow, thanks. Did not realize. (Also glad you are here, Firefox users should be helped a great deal! :)) – NightwishFan Oct 19 '10 at 20:04

Bannaz solution works great since I don't use .desktop files, but sometimes (or maybe every time) when I upgrade Firefox, my patch to the launcher script disappear.

So my solution to this is to create a new launcher script file which sets the preferred GTK theme, executes the original launcher script and does not get affected by an upgrade.

The original launcher on my system is located at /usr/bin/firefox.

I created a new launcher located at /usr/bin/local/firefox containing the following:

export GTK_THEME=Adwaita
exec /usr/bin/firefox "$@"

Change the path locations to suit your system. And don't forget to make it executable:

sudo chmod +x /usr/local/bin/firefox

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