The "official" way of translating WebExtensions content is the i18n API, which requires to define a key for each portion of text to translate.

This can be seen as brain consuming, especially in the case of a big web page, with lots of text parts, like a form. It’s the case of Meta-Press.es main interface, but also for its preferences, like a lot of other WebExtensions.

In order to get close of the standard GNU gettext way of translating programs, I decided to use Guillaume Potier’s gettext.js and to code the helper functions that was missing to:

Now Meta-Press.es is available in English, French, Spanish and Esperanto !

To contribute a new language, you have just to fill the blanks in the templace.json file of the Meta-Press.es project, and create a pull-request (or send it via email).

If you’re looking for a simple way of translation / internationalisation for your Firefox Addon project (or a least your option page), I shared the dedicated code as a separate project in the gettext_html_auto.js repository, along with some documentation. You would be welcome to use it.

With month_nb, it’s the 2nd side project made for Meta-Press.es.