diff --git a/lib/ace/mode/folding/mixed.js b/lib/ace/mode/folding/mixed.js
index 40d2cda8..3dd48a7d 100644
--- a/lib/ace/mode/folding/mixed.js
+++ b/lib/ace/mode/folding/mixed.js
@@ -59,6 +59,8 @@ oop.inherits(FoldMode, BaseFoldMode);
     };
 
     this.getFoldWidget = function(session, foldStyle, row) {
+        if (session.bgTokenizer.currentLine < row)
+            return;
         return (
             this.$tryMode(session.getState(row-1), session, foldStyle, row) ||
             this.$tryMode(session.getState(row), session, foldStyle, row) ||