diff --git a/library/HTMLPurifier/Filter/ExtractStyleBlocks.php b/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
index 8d781946..66f70b0f 100644
--- a/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
+++ b/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
@@ -95,6 +95,9 @@ class HTMLPurifier_Filter_ExtractStyleBlocks extends HTMLPurifier_Filter
         if ($tidy !== null) {
             $this->_tidy = $tidy;
         }
+        // NB: this must be NON-greedy because if we have
+        // <style>foo</style>  <style>bar</style>
+        // we must not grab foo</style>  <style>bar
         $html = preg_replace_callback('#<style(?:\s.*)?>(.*)<\/style>#isU', array($this, 'styleCallback'), $html);
         $style_blocks = $this->_styleMatches;
         $this->_styleMatches = array(); // reset