diff --git a/wp-includes/ms-files.php b/wp-includes/ms-files.php
index 5f969bf456..de6d15dbdd 100644
--- a/wp-includes/ms-files.php
+++ b/wp-includes/ms-files.php
@@ -57,8 +57,8 @@ header( "Last-Modified: $last_modified GMT" );
 header( 'ETag: ' . $etag );
 header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', time() + 100000000 ) . ' GMT' );
 
-// Support for Conditional GET
-$client_etag = isset( $_SERVER['HTTP_IF_NONE_MATCH'] ) ? wp_unslash( $_SERVER['HTTP_IF_NONE_MATCH'] ) : false;
+// Support for Conditional GET - use stripslashes to avoid formatting.php dependency
+$client_etag = isset( $_SERVER['HTTP_IF_NONE_MATCH'] ) ? stripslashes( $_SERVER['HTTP_IF_NONE_MATCH'] ) : false;
 
 if( ! isset( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) )
 	$_SERVER['HTTP_IF_MODIFIED_SINCE'] = false;