diff --git a/frontend-js/package.json b/frontend-js/package.json
index 68b9ecf5edd8298c606e7cb6444aca2c469ae68f..432f0545aeea0a09526a386b3c777706ccfd820e 100644
--- a/frontend-js/package.json
+++ b/frontend-js/package.json
@@ -12,7 +12,6 @@
   "author": "Piotr Gawron",
   "devDependencies": {
     "assert": "1.4.1",
-    "blob-util": "^1.2.1",
     "bluebird": "^3.4.6",
     "bootstrap": "^3.3.7",
     "browserify": "^13.1.1",
diff --git a/frontend-js/src/main/js/gui/OverlayPanel.js b/frontend-js/src/main/js/gui/OverlayPanel.js
index 10703fffc6288bd03aeeab1812f45a16c5117f47..2038a7345c071a50ff11f5aa35814f0d741187f7 100644
--- a/frontend-js/src/main/js/gui/OverlayPanel.js
+++ b/frontend-js/src/main/js/gui/OverlayPanel.js
@@ -39,7 +39,7 @@ function OverlayPanel(params) {
   } else {
     self.getAddButtonElement().onclick = function(){
       self.openAddOverlayDialog();
-    }
+    };
   }
 
   self.setCustomOverlaysMessage(self.getCustomOverlaysTitleElement().innerHTML);
@@ -338,7 +338,7 @@ OverlayPanel.prototype.parseFile = function(fileContent) {
 OverlayPanel.prototype.openAddOverlayDialog = function() {
   var self = this;
   var fileContent = null;
-  return new Promise(function(resolve, reject){
+  return new Promise(function(resolve){
 
     var content = document.createElement("div");
     content.style.width="100%";
@@ -377,10 +377,10 @@ OverlayPanel.prototype.openAddOverlayDialog = function() {
           if (data.description!==undefined) {
             descriptionInput.value =data.description; 
           }
-        }
-        reader.onerror = function (evt) {
+        };
+        reader.onerror = function () {
           GuiConnector.alert("Problem reading file");
-        }
+        };
       }
     }, false);
     content.appendChild(fileInput);
@@ -398,7 +398,7 @@ OverlayPanel.prototype.openAddOverlayDialog = function() {
               description : descriptionInput.value,
               content : fileContent,
               filename : fileInput.value
-          }          
+          };          
           return ServerConnector.addOverlay(data).then(function(){
             return self.refresh();
           }).then(function(){
diff --git a/frontend-js/src/main/js/gui/Panel.js b/frontend-js/src/main/js/gui/Panel.js
index d0eb10276e0158b50d736b219e5f7583279d86b7..4d0f5e111d5c536f048be81c4319e7687e964f37 100644
--- a/frontend-js/src/main/js/gui/Panel.js
+++ b/frontend-js/src/main/js/gui/Panel.js
@@ -6,7 +6,6 @@ var GuiConnector = require('../GuiConnector');
 var ObjectWithListeners = require('../ObjectWithListeners');
 
 var logger = require('../logger');
-var fun = require('../Functions');
 
 function Panel(params) {
   ObjectWithListeners.call(this, params);
diff --git a/frontend-js/src/test/js/gui/OverlayPanel-test.js b/frontend-js/src/test/js/gui/OverlayPanel-test.js
index d3053c6703343dccfa00b29ecc92b4e8c26751e7..c86798bb1800ec11b58062bc7c5299cd95898504 100644
--- a/frontend-js/src/test/js/gui/OverlayPanel-test.js
+++ b/frontend-js/src/test/js/gui/OverlayPanel-test.js
@@ -9,7 +9,6 @@ var OverlayPanel = require('../../../main/js/gui/OverlayPanel');
 var chai = require('chai');
 var assert = chai.assert;
 var logger = require('../logger');
-var blobUtil = require('blob-util');
 
 describe('OverlayPanel', function() {
 
diff --git a/frontend-js/src/test/js/gui/Panel-test.js b/frontend-js/src/test/js/gui/Panel-test.js
index 2579466646062bd242414474cd6ca8acfb4b7f52..5d952b5f93840359b84894054701fc67a98d94f7 100644
--- a/frontend-js/src/test/js/gui/Panel-test.js
+++ b/frontend-js/src/test/js/gui/Panel-test.js
@@ -1,10 +1,11 @@
 "use strict";
 
+/* exported logger */
+
 var Helper = require('../helper');
 
 require("../mocha-config.js");
 
-var Alias = require('../../../main/js/map/data/Alias');
 var Panel = require('../../../main/js/gui/Panel');
 
 var chai = require('chai');
diff --git a/frontend-js/src/test/js/mocha-config.js b/frontend-js/src/test/js/mocha-config.js
index 41279fa5d01c576fbd22bc3f56e39a276a27ff95..a584f89750fdaa7b056dce6724ceeea3d9b6dd66 100644
--- a/frontend-js/src/test/js/mocha-config.js
+++ b/frontend-js/src/test/js/mocha-config.js
@@ -17,7 +17,7 @@ global.$ = require('jQuery');
 global.jQuery = $;
 global.window.$ = $;
 
-require('jquery-ui-dist/jquery-ui.js')
+require('jquery-ui-dist/jquery-ui.js');
 
 require("bootstrap");