There are two ways of changing the language. An easy way by simply downloading the complete install of Firefox in your preferred language. If you have a slow internet connection this can take a while, but it doesn't involve changing any settings.
If your menu language mysteriously changed or you only want to add an additional language, there is a slightly more complex way by only downloading the language pack. This is a smaller and thus quicker download but involves make more changes.
The simple wayVisit the International versions page and download Firefox in your preferred language.
After the download is completed simply reinstall Firefox and the language should be updated.
The complex wayPlease note MyFireFox.co.uk is not related to Mozilla FireFox and any advice is given on a as-is basis without any warranty.
Download language packIf your menu language mysteriously changed you may be able to skip this step. If so, just go to the next step and if it doesn't work try again including this step.
Download the installer directly with your language if you haven't installed Firefox yet, or install additional dictionary languages and languages packs.
Change your language setting
- Open a new tab/window
- Type or copy/paste as the URL in the location bar.
You will see a list of configurable settings.
- Type (or copy/paste) into the filter field.
- Double click the value and enter the language code of the xpi file you installed. If you downloaded en-US.xpi type in en-US.
- Restart Firefox and you should see the menus in your new language.