diff --git a/db_graph.php b/db_graph.php
index 7acf792a..fba0909b 100644
--- a/db_graph.php
+++ b/db_graph.php
@@ -46,7 +46,7 @@ $token = $_SESSION['token'];
 
 <div class="row">
   <div class="col-md-12">
-    <div id="timeoutWarning" class="alert alert-warning alert-dismissible fade in" role="alert" hidden="true">
+    <div id="timeoutWarning" class="alert alert-warning alert-dismissible fade in" role="alert" hidden>
         Depending on how large of a range you specified, the request may time out while Pi-hole tries to retrieve all the data.<br/><span id="err"></span>
     </div>
   </div>
@@ -69,7 +69,7 @@ $token = $_SESSION['token'];
           </div>
         </div>
       </div>
-      <div class="overlay" hidden="true">
+      <div class="overlay" hidden>
         <i class="fa fa-sync fa-spin"></i>
       </div>
     </div>
diff --git a/db_lists.php b/db_lists.php
index f143f559..1161d731 100644
--- a/db_lists.php
+++ b/db_lists.php
@@ -49,7 +49,7 @@ $token = $_SESSION['token'];
   </div>
 </div>
 
-<div id="timeoutWarning" class="alert alert-warning alert-dismissible fade in" role="alert" hidden="true">
+<div id="timeoutWarning" class="alert alert-warning alert-dismissible fade in" role="alert" hidden>
     Depending on how large of a range you specified, the request may time out while Pi-hole tries to retrieve all the data.<br/><span id="err"></span>
 </div>
 
diff --git a/db_queries.php b/db_queries.php
index 776151dc..450a5ed0 100644
--- a/db_queries.php
+++ b/db_queries.php
@@ -71,7 +71,7 @@ $token = $_SESSION['token'];
     </div>
 </div>
 
-<div id="timeoutWarning" class="alert alert-warning alert-dismissible fade in" role="alert" hidden="true">
+<div id="timeoutWarning" class="alert alert-warning alert-dismissible fade in" role="alert" hidden>
     Depending on how large of a range you specified, the request may time out while Pi-hole tries to retrieve all the data.<br/><span id="err"></span>
 </div>
 
diff --git a/debug.php b/debug.php
index 116ed4ea..cf088bd3 100644
--- a/debug.php
+++ b/debug.php
@@ -15,7 +15,7 @@
 <input type="checkbox" id="upload"><label for="upload">Upload debug log and provide token once finished</label>
 <p>Once you click this button a debug log will be generated and can automatically be uploaded if we detect a working internet connection.</p>
 <button type="button" id="debugBtn" class="btn btn-lg btn-primary btn-block">Generate debug log</button>
-<pre id="output" style="width: 100%; height: 100%;" hidden="true"></pre>
+<pre id="output" style="width: 100%; height: 100%;" hidden></pre>
 
 <script src="scripts/pi-hole/js/debug.js"></script>
 
diff --git a/dns_records.php b/dns_records.php
index dbd6c55a..362329dc 100644
--- a/dns_records.php
+++ b/dns_records.php
@@ -46,19 +46,19 @@
 </div>
 
 <!-- Alerts -->
-<div id="alInfo" class="alert alert-info alert-dismissible fade in" role="alert" hidden="true">
+<div id="alInfo" class="alert alert-info alert-dismissible fade in" role="alert" hidden>
     <button type="button" class="close" data-hide="alert" aria-label="Close"><span aria-hidden="true">&times;</span></button>
     Updating the custom DNS entries...
 </div>
-<div id="alSuccess" class="alert alert-success alert-dismissible fade in" role="alert" hidden="true">
+<div id="alSuccess" class="alert alert-success alert-dismissible fade in" role="alert" hidden>
     <button type="button" class="close" data-hide="alert" aria-label="Close"><span aria-hidden="true">&times;</span></button>
     Success! The list will refresh.
 </div>
-<div id="alFailure" class="alert alert-danger alert-dismissible fade in" role="alert" hidden="true">
+<div id="alFailure" class="alert alert-danger alert-dismissible fade in" role="alert" hidden>
     <button type="button" class="close" data-hide="alert" aria-label="Close"><span aria-hidden="true">&times;</span></button>
     Failure! Something went wrong, see output below:<br/><br/><pre><span id="err"></span></pre>
 </div>
-<div id="alWarning" class="alert alert-warning alert-dismissible fade in" role="alert" hidden="true">
+<div id="alWarning" class="alert alert-warning alert-dismissible fade in" role="alert" hidden>
     <button type="button" class="close" data-hide="alert" aria-label="Close"><span aria-hidden="true">&times;</span></button>
     At least one domain was already present, see output below:<br/><br/><pre><span id="warn"></span></pre>
 </div>
diff --git a/gravity.php b/gravity.php
index 4ae73ebb..e0a46b7b 100644
--- a/gravity.php
+++ b/gravity.php
@@ -13,17 +13,17 @@
 </div>
 
 <!-- Alerts -->
-<div id="alInfo" class="alert alert-info alert-dismissible fade in" role="alert" hidden="true">
+<div id="alInfo" class="alert alert-info alert-dismissible fade in" role="alert" hidden>
     <button type="button" class="close" data-hide="alert" aria-label="Close"><span aria-hidden="true">&times;</span></button>
     Updating...this may take a while. <strong>Please do not navigate away from or close this page.</strong>
 </div>
-<div id="alSuccess" class="alert alert-success alert-dismissible fade in" role="alert" hidden="true">
+<div id="alSuccess" class="alert alert-success alert-dismissible fade in" role="alert" hidden>
     <button type="button" class="close" data-hide="alert" aria-label="Close"><span aria-hidden="true">&times;</span></button>
     Success!
 </div>
 
 <button type="button" id="gravityBtn" class="btn btn-lg btn-primary btn-block">Update</button>
-<pre id="output" style="width: 100%; height: 100%;" hidden="true"></pre>
+<pre id="output" style="width: 100%; height: 100%;" hidden></pre>
 
 <script src="scripts/pi-hole/js/gravity.js"></script>
 
diff --git a/queryads.php b/queryads.php
index aabff57e..437825a3 100644
--- a/queryads.php
+++ b/queryads.php
@@ -32,7 +32,7 @@
   </div>
 </div>
 
-<pre id="output" style="width: 100%; height: 100%;" hidden="true"></pre>
+<pre id="output" style="width: 100%; height: 100%;" hidden></pre>
 
 <script src="scripts/pi-hole/js/queryads.js"></script>
 
diff --git a/scripts/pi-hole/php/header.php b/scripts/pi-hole/php/header.php
index 45dd83b3..f73706b2 100644
--- a/scripts/pi-hole/php/header.php
+++ b/scripts/pi-hole/php/header.php
@@ -530,7 +530,7 @@ if($auth) {
                   </ul>
                 </li>
                 <!-- Toggle -->
-                <li id="pihole-disable" class="treeview"<?php if ($pistatus == "0") { ?> hidden="true"<?php } ?>>
+                <li id="pihole-disable" class="treeview"<?php if ($pistatus == "0") { ?> hidden<?php } ?>>
                   <a href="#">
                     <span class="pull-right-container">
                       <i class="fa fa-angle-left pull-right"></i>
@@ -566,7 +566,7 @@ if($auth) {
                   </ul>
                     <!-- <a href="#" id="flip-status"><i class="fa fa-stop"></i> <span>Disable</span></a> -->
                 </li>
-                <li id="pihole-enable" class="treeview"<?php if ($pistatus == "1") { ?> hidden="true"<?php } ?>>
+                <li id="pihole-enable" class="treeview"<?php if ($pistatus == "1") { ?> hidden<?php } ?>>
                     <a href="#">
                       <i class="fa fa-play"></i>
                       <span id="enableLabel">Enable&nbsp;&nbsp;&nbsp;