This is no longer required for the offline mode, since it is included in the generic template `rChart.html`. I might need to update the generic template to allow for a custom class. I am thinking of making it `class="rCharts {{ lib }}"`, so that we can use both generic and specific styles for each library. You would still need this in `script.html` until I push the next fix which will do away with `script.html` completely.