diff --git a/content-list.php b/content-list.php
index cd20398..65c820c 100644
--- a/content-list.php
+++ b/content-list.php
@@ -10,7 +10,7 @@
 					<?php if ( has_post_thumbnail() ): ?>
 						<?php the_post_thumbnail('agnar-medium'); ?>
 					<?php elseif ( get_theme_mod('placeholder') !='off' ): ?>
-						<img src="<?php echo get_template_directory_uri(); ?>/img/thumb-medium.png" alt="<?php the_title_attribute(); ?>" />
+						<img src="<?php echo esc_url( get_template_directory_uri() ); ?>/img/thumb-medium.png" alt="<?php the_title_attribute(); ?>" />
 					<?php endif; ?>
 					<?php if ( has_post_format('video') && !is_sticky() ) echo'<span class="thumb-icon"><i class="fas fa-play"></i></span>'; ?>
 					<?php if ( has_post_format('audio') && !is_sticky() ) echo'<span class="thumb-icon"><i class="fas fa-volume-up"></i></span>'; ?>
diff --git a/content.php b/content.php
index c6d476c..d97be16 100644
--- a/content.php
+++ b/content.php
@@ -10,7 +10,7 @@
 					<?php if ( has_post_thumbnail() ): ?>
 						<?php the_post_thumbnail('agnar-medium'); ?>
 					<?php elseif ( get_theme_mod('placeholder') !='off' ): ?>
-						<img src="<?php echo get_template_directory_uri(); ?>/img/thumb-medium.png" alt="<?php the_title_attribute(); ?>" />
+						<img src="<?php echo esc_url( get_template_directory_uri() ); ?>/img/thumb-medium.png" alt="<?php the_title_attribute(); ?>" />
 					<?php endif; ?>
 					<?php if ( has_post_format('video') && !is_sticky() ) echo'<span class="thumb-icon"><i class="fas fa-play"></i></span>'; ?>
 					<?php if ( has_post_format('audio') && !is_sticky() ) echo'<span class="thumb-icon"><i class="fas fa-volume-up"></i></span>'; ?>
diff --git a/inc/related-posts.php b/inc/related-posts.php
index 1ef0b6a..81bce30 100644
--- a/inc/related-posts.php
+++ b/inc/related-posts.php
@@ -17,7 +17,7 @@
 					<?php if ( has_post_thumbnail() ): ?>
 						<?php the_post_thumbnail('agnar-medium'); ?>
 					<?php elseif ( get_theme_mod('placeholder') !='off' ): ?>
-						<img src="<?php echo get_template_directory_uri(); ?>/img/thumb-medium.png" alt="<?php the_title_attribute(); ?>" />
+						<img src="<?php echo esc_url( get_template_directory_uri() ); ?>/img/thumb-medium.png" alt="<?php the_title_attribute(); ?>" />
 					<?php endif; ?>
 					<?php if ( has_post_format('video') && !is_sticky() ) echo'<span class="thumb-icon small"><i class="fas fa-play"></i></span>'; ?>
 					<?php if ( has_post_format('audio') && !is_sticky() ) echo'<span class="thumb-icon small"><i class="fas fa-volume-up"></i></span>'; ?>
diff --git a/style.css b/style.css
index f151867..d2e7891 100644
--- a/style.css
+++ b/style.css
@@ -4,6 +4,7 @@ Theme URI: http://alx.media/themes/agnar/
 Version: 2.2.1
 Requires at least: 5.0
 Requires PHP: 5.6
+Tested up to: 5.5
 Description: <a href="http://alx.media/themes/agnar/">Agnar</a> is a flexible theme for magazines and blogs. What makes it special is how well it scales all the way up to 1920px width and fill the entire screen beautifully, with a wall of visual posts. 
 Author: Alexander Agnarson
 Author URI: http://alx.media