Firefox 41: change translation engine from Bing to Yandex

Mozilla has been working on implementing translation functionality in the Firefox web browser for some time now. We mentioned it first here on ComTek back in mid-2014 when it was implemented in Nightly versions of the web browser.

The feature has yet to land in the stable version of the Firefox browser as it is still being worked on. One core difference to Google Chrome's implementation of a translation engine is that Mozilla's is not limited to a single service.

The first implementation in Firefox added Microsoft's Translation service powered by Bing to Firefox. Starting with Firefox 41, users of the browser may switch from using Microsoft's translation engine to the translation service provided by the Russian company Yandex.

The feature just landed in Firefox and there is no graphical user interface available to make the switch. Instead, it is necessary to make changes on the browser's about:config page.

Note: Yandex's Translate API is limited to ten million characters per month. It is unlikely that home users will come close to the limit though.

1. Make sure you are running Firefox 41 or later. You can display the browser version by loading about:support in the browser's address bar.
2. Type about:config and hit enter.
3. Confirm you will be careful if a notification prompt appears.
4. Search for the preference name browser.translation.engine.
5. Double-click on it and switch its value from bing to yandex.

Once done, visit Yandex's Translate API website to get a free API key. Please note that you need to sign up for an account on the site to do that. Sign-up does not require an email address or verification and should not take longer than a minute.

Once the API key has been generated (which is instant after account creation), continue with the steps outlined below:

1. On Firefox's about:config page, right-click on an empty spot in the main area and select New > String and enter browser.translation.yandex.apiKeyOverride as the string name.
2. When you are asked to select a value, enter the API key that was generated for you.

Check the about:preferences#content page in Firefox to make sure the translate feature is enabled in the browser. Please note that it will show "translations by Microsoft Translator even if you have switched the engine to Yandex using the about:config dialog of the browser.

Firefox displays a small prompt on foreign language pages from that moment on to translate web pages in the browser.

Configuration options are provided to block the prompt for select languages, and to select a default language that you want pages to be translated to. It is still possible to switch the default language using the prompt should the need arise.

Mozilla has yet to reveal when the feature will land in stable versions of the browser. You can track the meta bugs 971044 and 973271 for implementation information..