function showBrokenImageIcon() {
			editor.contentStyles.push(
				'img:-moz-broken {' +
					'-moz-force-broken-image-icon:1;' +
					'min-width:24px;' +
					'min-height:24px' +
				'}'
			);
		}
Forces Gecko to render a broken image icon if it fails to load an image.