Support javascript output

I'm trying to use hvega which outputs vega-lite plots. The output is a javascript block. However, when running the source block I get no output and a warning: Warning (emacs): No valid mimetype found (:application/javascript). This is when trying the barcode example in https://raw.githubusercontent.com/DougBurke/hvega/master/notebooks/VegaLiteGallery.ipynb Obviously the interactivity isn't needed, but having it at least print out the javascript string would be beneficial on export. Best case scenario would be to have :file automatically export to .svg and .png.

MESSAGE: (:iopub :display-data (:data (:application/javascript requirejs({paths:{vg:’https://cdn.jsdelivr.net/npm/vega@3.2.1/build/vega.min’,vl:’https://cdn.jsdelivr.net/npm/vega-lite@2.3.0/build/vega-lite.min’,vge:’https://cdn.jsdelivr.net/npm/vega-embed@3.5.2/build/vega-embed.min’},shim:{vge:{deps:[’vg.global’,’vl.global’]},vl:{deps:[’vg’]}}});define(’vg.global’,[’vg’],function(g){window.vega = g;});define(’vl.global’,[’vl’],function(g){window.vl = g;});var ndiv = document.createElement(’div’);ndiv.innerHTML = ’Awesome Vega-Lite visualization to appear here’;element[0].appendChild(ndiv);require([’vge’],function(vegaEmbed){vegaEmbed(ndiv,{"mark":"bar","data":{"values":[{"a":"A","b":28},{"a":"B","b":55},{"a":"C","b":43},{"a":"D","b":91},{"a":"E","b":81},{"a":"F","b":53},{"a":"G","b":19},{"a":"H","b":87},{"a":"I","b":52}]},"$schema":"https://vega.github.io/schema/vega-lite/v2.json","encoding":{"x":{"field":"a","type":"ordinal"},"y":{"field":"b","type":"quantitative"}},"description":"A simple bar chart with embedded data."}).then(function (result) { console.log(result); }).catch(function (error) { ndiv.innerHTML = ’There was an error: ’ + error; });});) :metadata nil))