diff --git a/templates/page.apps.php b/templates/page.apps.php
index d73ea6285..a756b84d0 100644
--- a/templates/page.apps.php
+++ b/templates/page.apps.php
@@ -39,6 +39,10 @@
 			<li><?php p($l->t('Many others like a music player, a password manager, a kanban app, a download manager or a markdown editor')); ?></li>
 
 		</ul>
-		<p class="details-link"><a href="<?php p(\OC::$server->getURLGenerator()->linkToRoute('settings.AppSettings.viewApps')); ?>" target="_blank"><?php p($l->t('Browse the app store')); ?></a></p>
+		<p class="details-link">
+			<a href="<?php p(\OC::$server->getURLGenerator()->linkToRoute('settings.AppSettings.viewApps')); ?>" target="_blank" rel="noreferrer noopener">
+				<?php p($l->t('Browse the app store')); ?>
+			</a>
+		</p>
 	</div>
 </div>
diff --git a/templates/page.clients.php b/templates/page.clients.php
index c3b77e87f..379bfcce3 100644
--- a/templates/page.clients.php
+++ b/templates/page.clients.php
@@ -34,16 +34,16 @@
 			<?php p($l->t('Our easy to use desktop and mobile clients are available for all major platforms at zero cost!')); ?></p>
 		<div class="description-block">
 			<h3><?php p($l->t('Get the apps to sync your files')); ?></h3>
-			<a target="_blank" href="<?php p($_['desktop']); ?>">
+			<a target="_blank" href="<?php p($_['desktop']); ?>" rel="noreferrer noopener">
 				<img src="<?php p(image_path('core', 'desktopapp.svg')); ?>"
 					 alt="<?php p($l->t('Desktop client')); ?>"/>
 			</a>
-			<a target="_blank" href="<?php p($_['android']); ?>">
+			<a target="_blank" href="<?php p($_['android']); ?>" rel="noreferrer noopener">
 				<img src="<?php p(image_path('core', 'googleplay.svg')); ?>"
 					 alt="<?php p($l->t('Android app')); ?>"
 					 style="height:60px"/>
 			</a>
-			<a target="_blank" href="<?php p($_['ios']); ?>">
+			<a target="_blank" href="<?php p($_['ios']); ?>" rel="noreferrer noopener">
 				<img src="<?php p(image_path('core', 'appstore.svg')); ?>"
 					 alt="<?php p($l->t('iOS app')); ?>" style="height:60px"/>
 			</a>
@@ -51,17 +51,17 @@
 		<div class="description-block">
 			<h3><?php p($l->t('Connect your desktop apps to %s', array($theme->getName()))); ?></h3>
 			<a target="_blank" class="button"
-			   href="<?php p(link_to_docs('user-sync-calendars')) ?>">
+			   href="<?php p(link_to_docs('user-sync-calendars')) ?>" rel="noreferrer noopener">
 				<span class="icon icon-calendar-dark"></span>
 				<?php p($l->t('Connect your calendar')); ?>
 			</a>
 			<a target="_blank" class="button"
-			   href="<?php p(link_to_docs('user-sync-contacts')) ?>">
+			   href="<?php p(link_to_docs('user-sync-contacts')) ?>" rel="noreferrer noopener">
 				<span class="icon icon-contacts-dark"></span>
 				<?php p($l->t('Connect your contacts')); ?>
 			</a>
 			<a target="_blank" class="button"
-			   href="<?php p(link_to_docs('user-webdav')); ?>">
+			   href="<?php p(link_to_docs('user-webdav')); ?>" rel="noreferrer noopener">
 				<span class="icon icon-files-dark"></span>
 				<?php p($l->t('Access files via WebDAV')); ?>
 			</a>
diff --git a/templates/page.final.php b/templates/page.final.php
index 38dec6fbd..333603ad0 100644
--- a/templates/page.final.php
+++ b/templates/page.final.php
@@ -12,14 +12,14 @@
 			<h3 class="icon-info"><?php p($l->t('Get more information')); ?></h3>
 			<p><?php p($l->t('The Nextcloud documentation for home users:')); ?></p>
 			<ul>
-				<li><a href="<?php p(link_to_docs('user-')) ?>"><?php p($l->t('User manual')); ?></a></li>
-				<li><a href="<?php p(link_to_docs('admin-')) ?>"><?php p($l->t('Admin manual')); ?></a></li>
-				<li><a href="<?php p(link_to_docs('developer-')) ?>"><?php p($l->t('Developer manual')); ?></a></li>
+				<li><a href="<?php p(link_to_docs('user-')) ?>" target="_blank" rel="noreferrer noopener"><?php p($l->t('User manual')); ?></a></li>
+				<li><a href="<?php p(link_to_docs('admin-')) ?>" target="_blank" rel="noreferrer noopener"><?php p($l->t('Admin manual')); ?></a></li>
+				<li><a href="<?php p(link_to_docs('developer-')) ?>" target="_blank" rel="noreferrer noopener"><?php p($l->t('Developer manual')); ?></a></li>
 			</ul>
 			<p><?php p($l->t('You can also ask for help in our community support channels:')); ?></p>
 			<ul>
-				<li><a href="https://help.nextcloud.com"><?php p($l->t('the Nextcloud forums')); ?></a></li>
-				<li><a href="https://riot.im/app/#/room/#freenode_#nextcloud:matrix.org"><?php p($l->t('the Nextcloud IRC chat channel on freenode.net')); ?></a></li>
+				<li><a href="https://help.nextcloud.com" target="_blank" rel="noreferrer noopener"><?php p($l->t('the Nextcloud forums')); ?></a></li>
+				<li><a href="https://riot.im/app/#/room/#freenode_#nextcloud:matrix.org" target="_blank" rel="noreferrer noopener"><?php p($l->t('the Nextcloud IRC chat channel on freenode.net')); ?></a></li>
 			</ul>
 		</div>
 	</div>
@@ -27,12 +27,12 @@
 		<div class="description-block">
 			<h3 class="icon-user"><?php p($l->t('Start contributing')); ?></h3>
 			<p><?php p($l->t('Do you want to get a certain improvement in Nextcloud? Did you find a problem? Do you want to help translate, promote or document Nextcloud?')); ?></p>
-			<a href="https://nextcloud.com/contribute/" class="button"><?php p($l->t('Become part of the Community')); ?></a>
+			<a href="https://nextcloud.com/contribute/" class="button" target="_blank" rel="noreferrer noopener"><?php p($l->t('Become part of the Community')); ?></a>
 		</div>
 		<div class="description-block">
 			<h3 class="icon-world"><?php p($l->t('Enterprise support')); ?></h3>
 			<p><?php p($l->t('If you run Nextcloud in a mission critical environment with large numbers of users and big amounts of data and need the certainty of support from the experts behind the Nextcloud technology, an Enterprise Subscription from Nextcloud is available with email and phone support.')); ?></p>
-			<a href="https://nextcloud.com/enterprise/buy" class="button"><?php p($l->t('Get enterprise support')); ?></a>
+			<a href="https://nextcloud.com/enterprise/buy" class="button"target="_blank" rel="noreferrer noopener" ><?php p($l->t('Get enterprise support')); ?></a>
 		</div>
 	</div>
 </div>
diff --git a/templates/page.values.php b/templates/page.values.php
index a9c3152fb..9222fbd83 100644
--- a/templates/page.values.php
+++ b/templates/page.values.php
@@ -49,6 +49,6 @@
 			</li>
 		</ul>
 
-		<p class="details-link"><a href="<?php p($theme->getBaseUrl()); ?>"><?php p($l->t('Learn more about %s', $theme->getName())); ?></a></p>
+		<p class="details-link"><a href="<?php p($theme->getBaseUrl()); ?>" target="_blank" rel="noreferrer noopener"><?php p($l->t('Learn more about %s', $theme->getName())); ?></a></p>
 	</div>
 </div>
diff --git a/templates/personal-settings.php b/templates/personal-settings.php
index 4872d6db7..0defd4b6e 100644
--- a/templates/personal-settings.php
+++ b/templates/personal-settings.php
@@ -33,15 +33,15 @@
 	<p><?php p($l->t('%s gives you access to your files wherever you are. Our easy to use desktop and mobile clients are available for all major platforms at zero cost.', [$theme->getName()])); ?></p>
 
 	<div class="clientslinks">
-		<a href="<?php p($_['clients']['desktop']); ?>" rel="noreferrer" target="_blank">
+		<a href="<?php p($_['clients']['desktop']); ?>" rel="noreferrer noopener" target="_blank">
 			<img src="<?php print_unescaped(image_path('core', 'desktopapp.svg')); ?>"
 				 alt="<?php p($l->t('Desktop client'));?>"/>
 		</a>
-		<a href="<?php p($_['clients']['android']); ?>" rel="noreferrer" target="_blank">
+		<a href="<?php p($_['clients']['android']); ?>" rel="noreferrer noopener" target="_blank">
 			<img src="<?php print_unescaped(image_path('core', 'googleplay.png')); ?>"
 				 alt="<?php p($l->t('Android app'));?>" />
 		</a>
-		<a href="<?php p($_['clients']['ios']); ?>" rel="noreferrer" target="_blank">
+		<a href="<?php p($_['clients']['ios']); ?>" rel="noreferrer noopener" target="_blank">
 			<img src="<?php print_unescaped(image_path('core', 'appstore.svg')); ?>"
 				 alt="<?php p($l->t('iOS app'));?>" />
 		</a>
@@ -57,17 +57,17 @@
 	<p><?php print_unescaped($l->t('Besides the sync clients you can connect any other software that supports the WebDAV/CalDAV/CardDAV protocols to %s.', [$theme->getName()])); ?></p>
 
 	<div class="clientslinks">
-		<a target="_blank" class="button" href="<?php p(link_to_docs('user-sync-calendars')) ?>">
+		<a target="_blank" class="button" href="<?php p(link_to_docs('user-sync-calendars')) ?>" rel="noreferrer noopener">
 			<img class="appsmall appsmall-calendar svg" alt=""
 				 src="<?php p(image_path('core', 'places/calendar.svg')); ?>" />
 			<?php p($l->t('Connect your calendar'));?>
 		</a>
-		<a target="_blank" class="button" href="<?php p(link_to_docs('user-sync-contacts')) ?>">
+		<a target="_blank" class="button" href="<?php p(link_to_docs('user-sync-contacts')) ?>" rel="noreferrer noopener">
 			<img class="appsmall appsmall-contacts svg" alt=""
 				 src="<?php p(image_path('core', 'places/contacts.svg')); ?>" />
 			<?php p($l->t('Connect your contacts'));?>
 		</a>
-		<a target="_blank" class="button" href="<?php p(link_to_docs('user-webdav')); ?>">
+		<a target="_blank" class="button" href="<?php p(link_to_docs('user-webdav')); ?>" rel="noreferrer noopener">
 			<img class="appsmall svg" alt=""
 				 src="<?php p(image_path('files', 'folder.svg')); ?>" />
 			<?php p($l->t('Access files via WebDAV'));?>