Edit: You can now preview the changes live. Also, the pull request got accepted!

I just submitted a GitHub PR for adding multilingual support to Mozilla’s HTML5 Sandstone slidedeck. The selection is persistent across slide changes, and in Firefox, the URL bar will update the lang attribute as well.

Pictures are worth thousands of words, so here you go:

Screenshot showing language menu dropdown

To add languages:

1. Add the style tags to the stylesheet
2. Modify the language menu
3. Place your translation within <div> tags with language code class names

Slide after language selection

Example code:

<div class=”en-US”>This is English.</div>
<div class=”zh-CN”>这是中文（简体）。</div>
<div class=”zh-TW”>這是中文（繁體）。</div>
<div class=”ja-JP”>これは日本語です。</div>

Next slide with persistent language selection change

If you would like to use this now, my changes are on a GitHub fork.

Massive thanks go out to :MattN who greatly helped me out. Thanks Matt!