diff --git a/library/Icinga/Util/LessParser.php b/library/Icinga/Util/LessParser.php
index 595332a30..946b3f686 100644
--- a/library/Icinga/Util/LessParser.php
+++ b/library/Icinga/Util/LessParser.php
@@ -4,10 +4,6 @@
 namespace Icinga\Util;
 
 use Icinga\Less\Visitor;
-use Less_Tree_Anonymous;
-use Less_Tree_Expression;
-use Less_Tree_Quoted;
-use Less_Tree_Value;
 use lessc;
 
 require_once 'lessphp/lessc.inc.php';
@@ -20,57 +16,8 @@ class LessParser extends lessc
      */
     public function __construct($disableModes = false)
     {
-        $this->registerFunction('extract-variable-default', [$this, 'extractVariableDefault']);
         if (! $disableModes) {
             $this->setOption('plugins', [new Visitor()]);
         }
     }
-
-    /**
-     * Extract default from given variable call
-     *
-     * How to use:
-     *
-     *   color: extract-variable-default(@mixin-parameter);
-     *   color: @mixin-parameter;
-     *
-     *   border: extract-variable-default(1px solid @mixin-parameter);
-     *   border: 1px solid @mixin-parameter;
-     *
-     *   background: drop-shadow(5px 0 3px extract-variable-default(@mixin-parameter, true));
-     *   background: drop-shadow(5px 0 3px @mixin-parameter);
-     *
-     * @param mixed $value
-     * @param bool  $valAsDefault
-     *
-     * @return mixed
-     */
-    public function extractVariableDefault($value, $valAsDefault = false)
-    {
-        $defaultValue = 'inherit';
-        if ($value instanceof Less_Tree_Quoted) {
-            $stripped = preg_replace(
-                '~var\s*\(\s*[-\w]+\s*,\s*([^)]+)\)~',
-                '$1',
-                $value->value,
-                -1,
-                $replacements
-            );
-            if ($replacements > 0) {
-                $defaultValue = $stripped;
-            }
-        } elseif ($value instanceof Less_Tree_Expression) {
-            foreach ($value->value as $i => $item) {
-                $value->value[$i] = $this->extractVariableDefault($item, true);
-            }
-
-            return $value;
-        }
-
-        if ($valAsDefault && $defaultValue === 'inherit') {
-            return $value;
-        }
-
-        return new Less_Tree_Value([new Less_Tree_Anonymous($defaultValue)]);
-    }
 }