re-included URL encoded characters within _remove_invisible_characters() which were mistakenly pulled out in a previous commit, not released
diff --git a/system/libraries/Input.php b/system/libraries/Input.php
index 7465021..24c6c19 100644
--- a/system/libraries/Input.php
+++ b/system/libraries/Input.php
@@ -828,8 +828,10 @@
 		

 		if ( ! isset($non_displayables))

 		{

-			// every control character except newline (10), carriage return (13), and horizontal tab (09),

+			// every control character except newline (dec 10), carriage return (dec 13), and horizontal tab (dec 09),

 			$non_displayables = array(

+										'/%0[0-8bcef]/',			// url encoded 00-08, 11, 12, 14, 15

+										'/%1[0-9a-f]/',				// url encoded 16-31

 										'/[\x00-\x08]/',			// 00-08

 										'/\x0b/', '/\x0c/',			// 11, 12

 										'/[\x0e-\x1f]/'				// 14-31