diff --git a/scripts/codemirror/lib/codemirror.js b/scripts/codemirror/lib/codemirror.js
index 88a9324..69b5c67 100644
--- a/scripts/codemirror/lib/codemirror.js
+++ b/scripts/codemirror/lib/codemirror.js
@@ -3342,7 +3342,7 @@
         prevBottom = bot;
       } else {
         var box = cur.node.getBoundingClientRect();
-        height = box.bottom - box.top;
+        height = box.bottom - box.top + 1;
         // Check that lines don't extend past the right of the current
         // editor width
         if (!wrapping && cur.text.firstChild)