Custom Store/Load using a Json object, without using the "Storage" API

I think I got it using:

let exportToLoad;

let editor = grapesjs.init({
    // ...
    storageManager: { 
        type: 'simpleStorage' 
    }
});

editor.StorageManager.add('simpleStorage', {
    load(keys, clb, clbErr) {
        if(exportToLoad) {
            clb(exportToLoad);
        }
    },
    store(data, clb, clbErr) {
      return data;
    }
});

function importFrom(exportContent) {
    exportToLoad = exportContent;
    editor.load(() => {});
},

Then:

let export = editor.store();

And:

importFrom(export);

That said, it doesn't feel totaly "right" to me. I would like a version of the functions where you can specify the exported Json object directly!

Using custom storage is actually the best way

I would like a version of the functions where you can specify the exported Json object directly!

Well, no one limits you to update your exportToLoad