diff --git a/library/Icinga/Application/webrouter.php b/library/Icinga/Application/webrouter.php
index 9eb5bf6f8..47210808e 100644
--- a/library/Icinga/Application/webrouter.php
+++ b/library/Icinga/Application/webrouter.php
@@ -56,12 +56,10 @@ if (in_array($path, $special)) {
 
     switch ($path) {
         case 'css/icinga.css':
-            $forIe11 = (bool) preg_match('/Trident\/7.0;.*rv:11/', $_SERVER['HTTP_USER_AGENT']);
-            Stylesheet::send(false, $forIe11);
+            Stylesheet::send();
             exit;
         case 'css/icinga.min.css':
-            $forIe11 = (bool) preg_match('/Trident\/7.0;.*rv:11/', $_SERVER['HTTP_USER_AGENT']);
-            Stylesheet::send(true, $forIe11);
+            Stylesheet::send(true);
             exit;
 
         case 'js/icinga.dev.js':
diff --git a/library/Icinga/Util/LessParser.php b/library/Icinga/Util/LessParser.php
index 946b3f686..46aa061f5 100644
--- a/library/Icinga/Util/LessParser.php
+++ b/library/Icinga/Util/LessParser.php
@@ -10,14 +10,8 @@ require_once 'lessphp/lessc.inc.php';
 
 class LessParser extends lessc
 {
-    /**
-     * @param bool $disableModes Disable replacing compiled Less colors with CSS var() function calls and don't inject
-     *                           light mode calls
-     */
-    public function __construct($disableModes = false)
+    public function __construct()
     {
-        if (! $disableModes) {
-            $this->setOption('plugins', [new Visitor()]);
-        }
+        $this->setOption('plugins', [new Visitor()]);
     }
 }
diff --git a/library/Icinga/Web/LessCompiler.php b/library/Icinga/Web/LessCompiler.php
index a47ca95af..1f72560bb 100644
--- a/library/Icinga/Web/LessCompiler.php
+++ b/library/Icinga/Web/LessCompiler.php
@@ -58,13 +58,10 @@ class LessCompiler
 
     /**
      * Create a new LESS compiler
-     *
-     * @param bool $disableModes Disable replacing compiled Less colors with CSS var() function calls and don't inject
-     *                           light mode calls
      */
-    public function __construct($disableModes = false)
+    public function __construct()
     {
-        $this->lessc = new LessParser($disableModes);
+        $this->lessc = new LessParser();
         // Discourage usage of import because we're caching based on an explicit list of LESS files to compile
         $this->lessc->importDisabled = true;
     }
diff --git a/library/Icinga/Web/StyleSheet.php b/library/Icinga/Web/StyleSheet.php
index 02087302d..2b46b5d35 100644
--- a/library/Icinga/Web/StyleSheet.php
+++ b/library/Icinga/Web/StyleSheet.php
@@ -106,15 +106,12 @@ class StyleSheet
 
     /**
      * Create the StyleSheet
-     *
-     * @param bool $disableModes Disable replacing compiled Less colors with CSS var() function calls and don't inject
-     *                           light mode calls
      */
-    public function __construct($disableModes = false)
+    public function __construct()
     {
         $app = Icinga::app();
         $this->app = $app;
-        $this->lessCompiler = new LessCompiler($disableModes);
+        $this->lessCompiler = new LessCompiler();
         $this->pubPath = $app->getBaseDir('public');
         $this->collect();
     }
@@ -224,13 +221,11 @@ class StyleSheet
      *
      * Does not cache the stylesheet if the HTTP header Cache-Control or Pragma is set to no-cache.
      *
-     * @param bool $minified     Whether to compress the stylesheet
-     * @param bool $disableModes Disable replacing compiled Less colors with CSS var() function calls and don't inject
-     *                           light mode calls
+     * @param   bool    $minified   Whether to compress the stylesheet
      */
-    public static function send($minified = false, $disableModes = false)
+    public static function send($minified = false)
     {
-        $styleSheet = new self($disableModes);
+        $styleSheet = new self();
 
         $request = $styleSheet->app->getRequest();
         $response = $styleSheet->app->getResponse();