diff --git a/app/assets/javascripts/utilities/browserStoreCache.js b/app/assets/javascripts/utilities/browserStoreCache.js
index 6c6fa334a..9db0977bb 100644
--- a/app/assets/javascripts/utilities/browserStoreCache.js
+++ b/app/assets/javascripts/utilities/browserStoreCache.js
@@ -1,3 +1,5 @@
+'use strict';
+
 function browserStoreCache(action, userData) {
   try {
     switch (action) {
@@ -19,4 +21,5 @@ function browserStoreCache(action, userData) {
       browserStoreCache('remove');
     }
   }
+  return undefined;
 }
diff --git a/app/assets/javascripts/utilities/checkUserLoggedIn.js b/app/assets/javascripts/utilities/checkUserLoggedIn.js
index 1bd909af6..1eb954397 100644
--- a/app/assets/javascripts/utilities/checkUserLoggedIn.js
+++ b/app/assets/javascripts/utilities/checkUserLoggedIn.js
@@ -1,3 +1,5 @@
+'use strict';
+
 function checkUserLoggedIn() {
   const body = document.getElementsByTagName('body')[0];
   if (!body) {
diff --git a/app/assets/javascripts/utilities/createAjaxReq.js b/app/assets/javascripts/utilities/createAjaxReq.js
index 8d4cdd848..74cd226ee 100644
--- a/app/assets/javascripts/utilities/createAjaxReq.js
+++ b/app/assets/javascripts/utilities/createAjaxReq.js
@@ -1,7 +1,8 @@
+'use strict';
+
 function createAjaxReq() {
   if (window.XMLHttpRequest) {
     return new XMLHttpRequest();
-  } else {
-    return new ActiveXObject("Microsoft.XMLHTTP");
   }
+  return new window.ActiveXObject('Microsoft.XMLHTTP');
 }
diff --git a/app/assets/javascripts/utilities/getCurrentPage.js b/app/assets/javascripts/utilities/getCurrentPage.js
index f4b078e0f..706afe0b1 100644
--- a/app/assets/javascripts/utilities/getCurrentPage.js
+++ b/app/assets/javascripts/utilities/getCurrentPage.js
@@ -1,3 +1,8 @@
+'use strict';
+
 function getCurrentPage(classString) {
-    return document.querySelectorAll("[data-current-page='"+classString+"']").length > 0
-}
\ No newline at end of file
+  return (
+    document.querySelectorAll("[data-current-page='" + classString + "']")
+      .length > 0
+  );
+}
diff --git a/app/assets/javascripts/utilities/getImageForLink.js b/app/assets/javascripts/utilities/getImageForLink.js
index eaaf9e592..fa1c56e46 100644
--- a/app/assets/javascripts/utilities/getImageForLink.js
+++ b/app/assets/javascripts/utilities/getImageForLink.js
@@ -1,7 +1,9 @@
+'use strict';
+
 var $fetchedImageUrls = [];
-function getImageForLink(elem){
-  var imageUrl = elem.getAttribute('data-preload-image')
-  if (imageUrl && $fetchedImageUrls.indexOf(imageUrl) == -1) {
+function getImageForLink(elem) {
+  var imageUrl = elem.getAttribute('data-preload-image');
+  if (imageUrl && $fetchedImageUrls.indexOf(imageUrl) === -1) {
     var img = new Image();
     img.src = imageUrl;
     $fetchedImageUrls.push(imageUrl);
diff --git a/app/assets/javascripts/utilities/insertAfter.js b/app/assets/javascripts/utilities/insertAfter.js
index ee78c88af..ec83911e8 100644
--- a/app/assets/javascripts/utilities/insertAfter.js
+++ b/app/assets/javascripts/utilities/insertAfter.js
@@ -1,5 +1,7 @@
+'use strict';
+
 function insertAfter(newNode, referenceNode) {
-    if (referenceNode && referenceNode.parentNode){
-      referenceNode.parentNode.insertBefore(newNode, referenceNode.nextSibling);
-    }
+  if (referenceNode && referenceNode.parentNode) {
+    referenceNode.parentNode.insertBefore(newNode, referenceNode.nextSibling);
+  }
 }
diff --git a/app/assets/javascripts/utilities/localDateTime.js b/app/assets/javascripts/utilities/localDateTime.js
index ad3bc5606..4c8060939 100644
--- a/app/assets/javascripts/utilities/localDateTime.js
+++ b/app/assets/javascripts/utilities/localDateTime.js
@@ -1,3 +1,5 @@
+'use strict';
+
 /* Local date/time utilities */
 
 /*
diff --git a/app/assets/javascripts/utilities/localStorageTest.js b/app/assets/javascripts/utilities/localStorageTest.js
index 0b096b676..607576ef9 100644
--- a/app/assets/javascripts/utilities/localStorageTest.js
+++ b/app/assets/javascripts/utilities/localStorageTest.js
@@ -1,10 +1,12 @@
-function localStorageTest(){
-    var test = 'devtolocalstoragetestforavaialbility';
-    try {
-        localStorage.setItem(test, test);
-        localStorage.removeItem(test);
-        return true;
-    } catch(e) {
-        return false;
-    }
+'use strict';
+
+function localStorageTest() {
+  var test = 'devtolocalstoragetestforavaialbility';
+  try {
+    localStorage.setItem(test, test);
+    localStorage.removeItem(test);
+    return true;
+  } catch (e) {
+    return false;
+  }
 }
diff --git a/app/assets/javascripts/utilities/preventDefaultAction.js b/app/assets/javascripts/utilities/preventDefaultAction.js
index 428ba9b53..73dfc2798 100644
--- a/app/assets/javascripts/utilities/preventDefaultAction.js
+++ b/app/assets/javascripts/utilities/preventDefaultAction.js
@@ -1,3 +1,5 @@
-function preventDefaultAction(event){
+'use strict';
+
+function preventDefaultAction(event) {
   event.preventDefault();
-}
\ No newline at end of file
+}