diff --git a/lib/common/collections/wp_items/detectable.rb b/lib/common/collections/wp_items/detectable.rb
index c84fd8b9..e0749f37 100644
--- a/lib/common/collections/wp_items/detectable.rb
+++ b/lib/common/collections/wp_items/detectable.rb
@@ -120,7 +120,7 @@ class WpItems < Array
       wp_content_dir = wp_target.wp_content_dir
       wp_content_url = wp_target.uri.merge(wp_content_dir).to_s
 
-      url = /#{wp_content_url.gsub(%r{\A(?:http|https)}, 'https?').gsub('/', '\\\\\?\/')}/i
+      url = wp_content_url.gsub(%r{\A(?:http|https)://}, '(?:https?:)?//').gsub('/', '\\\\\?\/')
       content_dir = %r{(?:#{url}|\\?\/\\?\/?#{wp_content_dir})}i
 
       %r{#{content_dir}\\?/#{type}\\?/}
diff --git a/spec/lib/common/collections/wp_items_spec.rb b/spec/lib/common/collections/wp_items_spec.rb
index 31d37988..a1c7414a 100644
--- a/spec/lib/common/collections/wp_items_spec.rb
+++ b/spec/lib/common/collections/wp_items_spec.rb
@@ -18,7 +18,7 @@ describe WpItems do
         vulnerable_targets_items: [ WpItem.new(uri, name: 'mr-smith'),
                                     WpItem.new(uri, name: 'neo')],
 
-        passive_detection: (1..13).reduce(WpItems.new) { |o, i| o << WpItem.new(uri, name: "detect-me-#{i}") }
+        passive_detection: (1..15).reduce(WpItems.new) { |o, i| o << WpItem.new(uri, name: "detect-me-#{i}") }
       }
     end
   end
diff --git a/spec/samples/common/collections/wp_items/detectable/passive_detection.html b/spec/samples/common/collections/wp_items/detectable/passive_detection.html
index 8e5fe7d6..06139300 100644
--- a/spec/samples/common/collections/wp_items/detectable/passive_detection.html
+++ b/spec/samples/common/collections/wp_items/detectable/passive_detection.html
@@ -19,6 +19,8 @@
 
   <script type='text/javascript' src='//wp-content/items/detect-me-5/main.js'></script>
 
+  <link rel='stylesheet' id='ai1ec_style-css'  href='//example.com/wp-content/items/detect-me-15/test.css' type='text/css' media='all' />
+
   <style type="text/css">
     #fancybox-loading.fancybox-ie div {
       background: transparent;
@@ -32,6 +34,7 @@
     @import url('/wp-content/items/detect-me-8/css/datatables.css?ver=1.9.4');
     @import url(/wp-content/items/detect-me-9/css/datatables.css?ver=1.9.4);
     @import url(//wp-content/items/detect-me-10/css/datatables.css?ver=1.9.4);
+    @import url(//example.com/wp-content/items/detect-me-14/css/datatables.css?ver=1.9.4);
     /* ]]> */
   </style>