diff --git a/frontend-js/src/main/js/gui/AddOverlayDialog.js b/frontend-js/src/main/js/gui/AddOverlayDialog.js
index 2e4cd33aa17e91782800ecb7cb82aacb18b12ac6..8d730471ae36be7564ed0b13bdb6f4778a0c8c91 100644
--- a/frontend-js/src/main/js/gui/AddOverlayDialog.js
+++ b/frontend-js/src/main/js/gui/AddOverlayDialog.js
@@ -179,8 +179,13 @@ AddOverlayDialog.prototype.addOverlay = function () {
   });
 };
 
+/**
+ *
+ * @returns {PromiseLike}
+ */
 AddOverlayDialog.prototype.destroy = function () {
   $(this.getElement()).dialog("destroy");
+  return Promise.resolve();
 };
 
 AddOverlayDialog.prototype.open = function () {
diff --git a/frontend-js/src/main/js/gui/leftPanel/OverlayPanel.js b/frontend-js/src/main/js/gui/leftPanel/OverlayPanel.js
index 7ccaf090ba708810c7134fcc8e79769d0d59eb08..f9e95e7d3cbf3ae47715a008afa4baad76f4a787 100644
--- a/frontend-js/src/main/js/gui/leftPanel/OverlayPanel.js
+++ b/frontend-js/src/main/js/gui/leftPanel/OverlayPanel.js
@@ -173,10 +173,13 @@ OverlayPanel.prototype.clear = function () {
 
 /**
  *
- * @param {boolean} edit
+ * @param {boolean} [edit=false]
  * @returns {HTMLElement}
  */
 OverlayPanel.prototype.createTableHeader = function (edit) {
+  if (edit === undefined) {
+    edit = false;
+  }
   var result = document.createElement("thead");
 
   var row = document.createElement("tr");
@@ -363,10 +366,13 @@ OverlayPanel.prototype.openEditOverlayDialog = function (overlay) {
 
 /**
  *
- * @param {boolean} showDefault
+ * @param {boolean} [showDefault=false]
  * @returns {PromiseLike}
  */
 OverlayPanel.prototype.refresh = function (showDefault) {
+  if (showDefault === undefined) {
+    showDefault = false;
+  }
   var self = this;
   var user = null;
 
@@ -439,7 +445,7 @@ OverlayPanel.prototype.refresh = function (showDefault) {
       title.innerHTML = self.getCustomOverlaysMessage();
       addButton.style.display = "block";
 
-      table = $(tableElement).on('order.dt', function (e) {
+      table = $(tableElement).on('order.dt', function () {
         if ($(tableElement).dataTable().fnSettings().aaSorting[0][0] === 0) {
           table.rowReorder.enable();
         } else {
@@ -544,7 +550,7 @@ OverlayPanel.prototype.init = function () {
     info: false,
     rowReorder: true
   });
-  table.on('row-reorder', function (e, diff, edit) {
+  table.on('row-reorder', function (e, diff) {
     var promises = [];
 
     for (var i = 0, ien = diff.length; i < ien; i++) {