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Can we change the interface language of Firefox?

  • 7 replies
  • 59 have this problem
  • 119 views
  • Last reply by ffw62

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Hi, I am not able to find a way to change the interface language of Firefox. Is there any way to change the language that Firefox interface/GUI is displayed.

Is downloading and installing the Firefox with the language the only solution?

Hi, I am not able to find a way to change the interface language of Firefox. Is there any way to change the language that Firefox interface/GUI is displayed. Is downloading and installing the Firefox with the language the only solution?

Chosen solution

rat wrote:

Is downloading and installing the Firefox with the language the only solution?

It's the preferred solution.

If you need to switch between different interface languages,

  1. Install the language pack for the desired languages.
  2. Type about:config into the address bar and press Enter.
  3. To bypass the warning, press the big button labeled "I'll be careful, I promise!".
  4. In the search box, paste intl.locale.matchOS
  5. In the search results, if intl.locale.matchOS is set to true, double-click it to set its value to false.
  6. In the search box, paste general.useragent.locale
  7. In the search results, double-click general.useragent.locale and set its value to the desired language.
  8. Restart Firefox for the change to take effect.

If you need to switch languages frequently, you may want to get an add-on like Simple Locale Switcher.

Read this answer in context 👍 15

All Replies (7)

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Chosen Solution

rat wrote:

Is downloading and installing the Firefox with the language the only solution?

It's the preferred solution.

If you need to switch between different interface languages,

  1. Install the language pack for the desired languages.
  2. Type about:config into the address bar and press Enter.
  3. To bypass the warning, press the big button labeled "I'll be careful, I promise!".
  4. In the search box, paste intl.locale.matchOS
  5. In the search results, if intl.locale.matchOS is set to true, double-click it to set its value to false.
  6. In the search box, paste general.useragent.locale
  7. In the search results, double-click general.useragent.locale and set its value to the desired language.
  8. Restart Firefox for the change to take effect.

If you need to switch languages frequently, you may want to get an add-on like Simple Locale Switcher.

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Thanks for the reply.

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As for ME.. it did not work. 1. for English US there is no language pack to be downloaded, likely it is already installed. Available only: English (US) English (US) Install Dictionary (247.6 kB)

2. I did set : intl.locale.matchOS to True 3. I did change: general.useragent.locale to EN 4. Under Options Contents I even moved language [en] to top

Closed/restarted Firefox (v33.0) Interface language remained Dutch.

Yes, Google changed, but not the Firefox GUI (like settings, etc) =

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Changing the user agent won't help if you do not have that language version of Firefox installed. You need to install the en-US Firefox version.

You can find the full version of the current Firefox 33.0.3 release in all languages and for all Operating Systems here:

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Thanks!

Well, then the '2nd option' in the first reply under 'If you need to switch between different interface languages' - I guess this is not entirely correct then?

Maybe one day that option will indeed be available, i.e. without having to install a totally different new Firefox...  :-)

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This only applies to language packs that are installed in the current Firefox profile folder if this isn't about the locale that you have installed. If you have a Dutch (nl) Firefox version and no English language pack(s) then you can't switch to the English language. You would either have to install the English Firefox version or an en-US language pack if you want to be able to switch between languages. If you have ended up with the wrong language for some reason, possibly after an update, then you need to install a full version of your preferred language.

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Please would you have a look at the above screenshot, a few postings back. I am not familiar with this, but for me... it looks like English is available (?) Then again, I may very well be mistaken.

Regretfully I can not download EN language pack, it is not listed. Other language packs are listed and downloadable alright, not English. I can download a English US Dictionary pack only though. (That is the reason for me to assume English is already installed?)

Thanks. -

Modified by ffw62