Asset Manger not updating

I've read the API and it says that we can filter assets by attributes. Cool! but I'm having trouble getting the asset manager to update:

I'm running the following:

editor.on('component:selected', component => {
	const am = editor.AssetManager;
				
	let assets = am.getAll().filter(
		asset => asset.get('category') == 'cat-1'
	);

	console.log("Img in Cat-1: " + assets.length);
	am.render(assets);
});

I have 2 images loading in my asset manager on editor.init -

grapesjs.init({
    assetManager: {
        assets: [
            {category: "cat-0", src: "img.jpg", width: "x", height: "x"},
            {category: "cat-1", src: "img.jpg", width: "x", height: "x"},
        ]
    },
});

both images have the attribute:

category: 'cat-X'

I want to just load cat-1 but this just doesn't work. Console logging works fine and returns the item but the attribute manager doesn't. What am I doing wrong?

Thanks