Drag image to canvas doesn't show image

Running latest version (0.14.29) on local server. Using the example webpage preset. Ubuntu 18.04, Chromium 69.

I got a problem dragging images to the canvas. I'm using a php backend. The image is uploaded and added to the assetmanager but the image doesn't show up in the canvas, only the missing file icon and the name of the file uploaded.

I'm using the demo page as a base. https://grapesjs.com/demo.html To test it replace asset manager in that file with:

// all_files is actually loaded via php, but the same error occurs if set to empty for testing.
var all_files = [];

		assetManager: {
			storageType: '',
			storeOnChange: true,
			storeAfterUpload: true,
			embedAsBase64: false,
			assets: all_files,
			noAssets: 'No assets here, drag to upload!',
			uploadFile: function (e) {
				console.log(arguments);
				var files = e.dataTransfer ? e.dataTransfer.files : e.target.files;
				var formData = new FormData();
				for (var i in files) {
					formData.append('file-' + i, files[i]);
				}
				$.ajax({
					url: '/file_upload',
					type: 'POST',
					data: formData,
					contentType: false,
					crossDomain: true,
					dataType: 'json',
					mimeType: "multipart/form-data",
					processData: false,
					success: function (result) {
						var images = result['data'];
						editor.AssetManager.add(images);
					}
				});
			},

			headers: {},
			params: {},
			autoAdd: 1,
			uploadText: 'Drop files here or click to upload.',
			addBtnText: 'Add image',
			dropzone: 0,
			openAssetsOnDrop: 0,
			dropzoneContent: '<div class="dropzone-inner">Drop media here.</div>',
			modalTitle: 'Select Image',
		},

The response from the server on upload looks like this: {"data":[{"id":"641","name":"myfile.jpg","type":"image","src":"\/remote\/file\/641","height":"0","width":"0"}]}

The element added to the canvas looks like this: <img data-gjs-type="image" alt="myfile.jpg" class="gjs-plh-image gjs-comp-selected" onmousedown="return false">

It's missing the src for the image.

Any idea what I'm doing wrong?

By the way, if i use the demo with local storage the drag n drop is working perfectly and the image is showing up.