Improving user experience for people all over the world

Kohei Yoshino

Every day, thousands of people visit from across the globe. As the hub site of the global Mozilla community, it has a variety of content including the Firefox download page which has been localized into 80+ languages — like Firefox itself — thanks to the tremendous contributions of volunteer localizers.

I can remember at an early age — a developer-oriented, documentation-centric geeky site. Some community members were translating those documents into their languages (I myself translated hundreds of docs to Japanese) but their work was done outside of the official site. As time passed, has become one of the most popular multilingual consumer sites on the Internet. is still under active development, though. With the increasing number of translations, how can visitors from around the world make the most of this content? In this article I’ll briefly explain some great new features I have contributed for the past few months that may lead to a better user experience for people who speak different languages.

Language Switcher is migrating from the original PHP-based site to the new Python-based robust platform called Bedrock. The legacy site had a language switcher at the bottom of each page, but there was a problem: the switcher showed all supported languages regardless of whether the current page was actually localized. When a user chose Français from the list but the page wasn’t translated into French, they were taken back to the original English page. That behavior confused them because the page just reloaded without changing anything.

The new language switcher on Bedrock only shows the localized languages for each page and works as expected. The number of the languages will continue to increase as localizers add new translations. (Bug 773371)

We believe we can improve the language switcher even further. A simple dropdown menu is accessible but difficult to use when the list becomes too long. Also, my recent research showed that the user experience on switching language was varied among the Mozilla properties. It’s obvious we need a better solution like the Tabzilla universal site navigation widget. (Bug 919869)

Search Engine Optimization

The Language Switcher is not a collection of links but rather a dropdown menu using <select>, so it cannot tell search engines about our localization. Googlebot and others are enough smart to mechanically submit such a simple form but they definitely prefer a better way to crawl.

We have implemented alternate URLs to solve the issue with just a little more HTML. Visit the home page and hit Ctrl+U (or Cmd+U) to view the source and find a list of <link rel="alternate" hreflang="x"> in the source. Search engines will recognize the list to show a localized page, if available, in their search results based on the searcher’s language. (Bug 481550)

We’ll also soon serve comprehensive XML sitemaps with the alternate URLs as part of our SEO efforts. (Bug 906882)

Translation Bar

This is the latest cool addition to You might have seen a similar functionality if you have installed Google Toolbar or the lovely Chrome browser. It may ask you if you’d like to translate a foreign-language page into your language with Google Translate. While it’s useful in general, the quality of the translation largely depends on the language. For example, Japanese, my mother tongue, is one of the most difficult languages for machine translation. Here at, we can enjoy the pages manually translated by native localizers, so why not offer our visitors the nicely localized page? That was the motivation for the new Translation Bar.

The implementation was straightforward. As described above, we already have the alternate, localized URLs in the page source. A script compares the browser locale (navigator.language) against the list, then shows the bar if the translation is available in that language. If the user selects Yes, please, he/she will be promptly redirected to the localized page. If the user selects No, thanks, sessionStorage will remember the preference and the bar will be hidden in the subsequent browsing session.

Of course, the labels on the bar are also localized. Visit a localized page to give it a try! The Translation Bar has just been deployed on and other Mozilla sites may adopt it soon. (Bug 906943)

Beyond Translation

As a Japanese Web developer and localizer, I do know localization is not just translation. Each language and country has a different culture, customs and perspectives. Under the Mozilla mission, the Web Production team is working hard to deliver a great experience for everyone. The ongoing challenges include localized news and promotions on the home page, better fonts for multibyte characters, layout improvements for RTL languages, and more. I’m very glad to help the team.

Mozilla is a lively, global, successful open-source community, and is not merely a corporate site. You can contribute in many ways, like me. Do you speak a language other than English? Be one of the awesome localizers! Did you find any bugs on or do you have any feedback on how to improve the site? Let us know via Bugzilla! Are you a Web developer with knowledge of HTML, CSS, JavaScript, or Python? Fork the GitHub repository, browse the bugs and send us pull requests!