Cannot read property 'XHRLoader' of undefined with vanilla JS build

Hello,

Getting this error message:

`Uncaught TypeError: Cannot read property 'XHRLoader' of undefined
at o (shaderfrog-runtime.min.js:1)
at n.load (shaderfrog-runtime.min.js:1)
at robo.js:136
at three.js:33659
at XMLHttpRequest. (three.js:30293)`

Line 136-139:
`runtime.load( 'Universe_In_A_Letter.json' , function (shaderData) {
var material = runtime.get(shaderData.name);
holoMesh.material = material;
});`

shaderfrog-runtime.min.js is included after three.js in index file. Any idea what's wrong?

Thanks