Error with wpdb::prepare

On this page: options-general.php?page=cjtoolbox there is a PHP error showing twice within each block. See screenshot.

The error is:
Warning: Missing argument 2 for wpdb::prepare(), called in <em>[removed]</em>/wp-content/plugins/css-javascript-toolbox/css-js-toolbox.php on line 895 and defined in <em>[removed]</em>/wp-includes/wp-db.php on line 990

From the source:

/**
		* Get code template selection list.
		*
		* @param string Type of template. It could be 'css' or 'js';
		* @param string Unique identified for the block list.
		* @return void
		*/
		function show_dropdown_box($type, $boxid) {
			global $wpdb;
			$query = $wpdb->prepare("SELECT id, title FROM {$wpdb->prefix}cjtoolbox_cjdata WHERE type = '{$type}'");
			$list = $wpdb->get_results($query);
			if(count($list)) {
				echo '<select id="cjtoolbox-'.$type.'-'.$boxid.'" class="cjtoolbox-'.$type.'">';
				foreach($list as $def) {
					echo '<option value="' . $def->id . '">'. $def->title . '</option>';
				}
				echo '</select>';
			}
		}

The line is:
$query = $wpdb->prepare("SELECT id, title FROM {$wpdb->prefix}cjtoolbox_cjdata WHERE type = '{$type}'");

My proposed solution:
$query = $wpdb->prepare("SELECT id, title FROM {$wpdb->prefix}cjtoolbox_cjdata WHERE type = %s", $type);

Let me know what you think.

http://ww.wp.xz.cn/extend/plugins/css-javascript-toolbox/