diff --git a/frontend-js/src/main/js/ServerConnector.js b/frontend-js/src/main/js/ServerConnector.js
index 8799fccfc45d327719c7ae464d4bce7d95dd8cfc..30be4d5fa9965f755f13b364ab1c55e361a10115 100644
--- a/frontend-js/src/main/js/ServerConnector.js
+++ b/frontend-js/src/main/js/ServerConnector.js
@@ -536,7 +536,7 @@ ServerConnector.setOverlayResultIds = function(overlayName, ids) {
 ServerConnector.sendOverlayDetailDataRequest = function(overlayName, identifiedElement, general) {
   var overlay = ServerConnector._overlays[overlayName];
   if (overlay === undefined) {
-    throw new Overlay("Unknown overlay: " + overlayName);
+    throw new Error("Unknown overlay: " + overlayName);
   }
   var functions = ServerConnector._overlayMethods[overlayName];
   if (functions !== undefined) {
@@ -1072,7 +1072,7 @@ ServerConnector.getLightAliases = function(aliasIds, projectId) {
   return this.getAliases(aliasIds,projectId,"id,bounds,modelId");
 };
 
-ServerConnector.getSessionData = function(aliasIds, projectId) {
+ServerConnector.getSessionData = function() {
   if (this._sessionData===undefined) {
     this._sessionData = new SessionData();
   }
diff --git a/frontend-js/src/main/js/map/CustomMap.js b/frontend-js/src/main/js/map/CustomMap.js
index 79bf66064047c534bb682acbde0e806aca456cf5..d0ab5c7f9e171556b4fd38ff431a91122c9fe244 100644
--- a/frontend-js/src/main/js/map/CustomMap.js
+++ b/frontend-js/src/main/js/map/CustomMap.js
@@ -440,7 +440,7 @@ CustomMap.prototype.refreshComments = function() {
   for ( var overlayName in this.overlayCollections) {
     if (this.overlayCollections.hasOwnProperty(overlayName) && overlayName === "comment") {
       var collection = this.overlayCollections[overlayName];
-      self.clearOverlayCollection(collection)
+      self.clearOverlayCollection(collection);
       if (ServerConnector.getSessionData().getShowComments()) {
         return collection.refresh().then(function(){
           return self.renderOverlayCollection({overlayCollection:collection});        
@@ -1725,7 +1725,7 @@ CustomMap.prototype.getTopOverviewImage = function() {
 CustomMap.prototype.addControl = function(element) {
   if (this._controls[element.id] !== undefined) {
     throw new Error("Element with id "+element.id+" already added to controls");
-  };
+  }
   if (ControlType[element.id]===undefined) {
     throw new Error("Unknown control type: "+element.id);
   }
diff --git a/frontend-js/src/test/js/SessionData-test.js b/frontend-js/src/test/js/SessionData-test.js
index 35de777e089ab7fd8d533348d06a80de95356f5c..67aa1e32c7c9212414437a58a0f0e924ca4cd614 100644
--- a/frontend-js/src/test/js/SessionData-test.js
+++ b/frontend-js/src/test/js/SessionData-test.js
@@ -23,5 +23,6 @@ describe('SessionData', function() {
     assert.ok(session.getShowComments());
     session.setShowComments(false);
     assert.notOk(session.getShowComments());
+    assert.equal(logger.getWarnings().length, 0);
   });
 });
diff --git a/frontend-js/src/test/js/map/overlay/CommentDbOverlay-test.js b/frontend-js/src/test/js/map/overlay/CommentDbOverlay-test.js
index 28c48f179e3685392f85fb0f5cab61db0537793a..c6c0fb5058ae15d3d9b366c28be484b1402b60c3 100644
--- a/frontend-js/src/test/js/map/overlay/CommentDbOverlay-test.js
+++ b/frontend-js/src/test/js/map/overlay/CommentDbOverlay-test.js
@@ -4,7 +4,6 @@ var Helper = require('../../Helper');
 var logger = require('../../logger');
 
 var CommentDbOverlay = require('../../../../main/js/map/overlay/CommentDbOverlay');
-var OverlayCollection = require('../../../../main/js/map/overlay/OverlayCollection');
 
 var assert = require('assert');
 
@@ -22,6 +21,8 @@ describe('CommentDbOverlay', function() {
     });
     assert.ok(oc);
     assert.equal(oc.getName(), 'test name');
+    
+    assert.equal(logger.getWarnings.length, 0);
   });
 
 });