Cannot read property 'indexOf' of undefined

I found a previous result here: https://github.com/artf/grapesjs/issues/1772 however I can still not get it to work, using the most basic setup, as per your guide, and the answer given in that question.

My script:

<script>
    jQuery(document).ready(function () {
        grapesjs.init({
            // Indicate where to init the editor. You can also pass an HTMLElement
            container: '#gjs',
            // Get the content for the canvas directly from the element
            // As an alternative we could use: `components: '<h1>Hello World Component!</h1>'`,
            components: '<h1>Hello World component!</h1>',
            storageManager: {type: null}
        });
    });
</script>

and the page is simply:

which results in

jquery.js:3827 Uncaught TypeError: Cannot read property 'indexOf' of undefined
    at grapes.js:6477
    at prototype.js:884
    at prototype.js:825
    at Array.forEach (<anonymous>)
    at Array.each (prototype.js:824)
    at Array.findAll (prototype.js:883)
    at unique (grapes.js:6476)
    at Init.find (grapes.js:7188)
    at child.render (grapes.js:48530)
    at child.addToCollection (grapes.js:48734)

and no functionality.

Any help/advise?