JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/handlebars.js/4.0.10/handlebars.js"></script>
<div id="output"></div>
<script type="template/handlebars" id="template">test</script>

JavaScript

function MyCompiler() {
  Handlebars.JavaScriptCompiler.apply(this, arguments);
}
MyCompiler.prototype = new Handlebars.JavaScriptCompiler();
// Use this compile to compile BlockStatment-Blocks
MyCompiler.prototype.compiler = MyCompiler
MyCompiler.prototype.nameLookup = function(parent, name, type) {
  if (type === 'context') {
    return this.source.functionCall('helpers.lookupLowerCase', '', [parent, JSON.stringify(name)])
  } else {
    return Handlebars.JavaScriptCompiler.prototype.nameLookup.call(this, parent, name, type);
  }
}

var env = Handlebars.create();
env.registerHelper('lookupLowerCase', function(parent, name) {
  return parent[name.toLowerCase()]
})
env.JavaScriptCompiler = MyCompiler;

var template = env.compile('{{#each Test}} ({{Value}}) {{/each}}');

document.getElementById('output').innerHTML = template({
  test: [ 
    {value: 'a'},
    {value: 'b'},
    {value: 'c'}
    ]
});