Even if you are not born in an English speaking country, you are still forced to use the computers in the English language. This is because most of the cool software are in English language and their translations are not so good in varying degrees. For example, Firefox is available in many locales like Japanese, Spanish, Tagalog, German but these locale translations look very funny in some places. Thus we are forced to use Firefox mainly in English most of the time. Even if you install a languages pack for your local language, the settings to switch between English and other languages are buried deep inside Firefox options and are very difficult to access. If you want to switch back and forth between different locales, then you can use the Zing! Locale Switcher extension.
The Zing! Locale Switcher extension installs an icon in the Firefox toolbar through which you can switch to any locale at any time as you see fit. In order to switch the locale, you can click on this Zing! Locale Switcher icon and select one for the languages from the drop-down menu that appears.
If the Zing! Locale Switcher extension is displaying only one language in the drop-down menu in your Firefox, then perhaps you have not installed any language packs for other locales. You can install languages packs in Firefox from the Mozilla website by visiting the languages tools section of Mozilla add-ons website.
As you select one of the languages from the Zing! Locale Switcher menu, you will be asked for confirmation in the target language. For example, I selected to switch to the Spanish (Spain) locale and it showed me the following confirmation box in the Spanish language.
After you select I Accept or (its equivalents in other languages), the Firefox browser restarts in the new locale. All the user interface would be shown in the selected locale – so be careful before experimenting with locales that you have no clue about. Imagine what would happen if you try out the Japanese locale without knowing any Japanese word other than Domo Arigato.
Conclusion: The Zing! Locale Switcher extension for Firefox allows you to switch back and forth between all the installed languages or locales in your Firefox browser. This is specially useful if you want to use Firefox in your local languages but are forced to use English because of your work.
You can download the Zing! Locale Switcher extension for Firefox from https://addons.mozilla.org/en-US/firefox/addon/zing-locale-switcher/.