diff --git a/CHANGELOG b/CHANGELOG
index a46a880bd..94e049409 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -44,7 +44,7 @@ Motions:
 - Bugfix: Several bugfixes regarding splitting list items in
   change recommendations [#3288].
 - Bugfix: Several bugfixes regarding diff version [#3407, #3408, #3410,
-  #3440, #3450, #3465, #3537, #3546, #3548, #3644].
+  #3440, #3450, #3465, #3537, #3546, #3548, #3644, #3656].
 - Added inline Editing for motion reason [#3361].
 - Added multiselect filter for motion comments [#3372].
 - Added support for pinning personal notes to the window [#3360].
diff --git a/openslides/motions/static/js/motions/linenumbering.js b/openslides/motions/static/js/motions/linenumbering.js
index 34006b202..964198dd9 100644
--- a/openslides/motions/static/js/motions/linenumbering.js
+++ b/openslides/motions/static/js/motions/linenumbering.js
@@ -538,7 +538,8 @@ angular.module('OpenSlidesApp.motions.lineNumbering', [])
                 newRoot = this.insertLineNumbersNode(html, lineLength, highlight, firstLine);
                 newHtml = newRoot.innerHTML;
             } else {
-                var cacheKey = this.djb2hash(lineLength.toString() + html);
+                var firstLineStr = (firstLine === undefined || firstLine === null ? '' : firstLine.toString());
+                var cacheKey = this.djb2hash(firstLineStr + "-" + lineLength.toString() + html);
                 newHtml = lineNumberCache.get(cacheKey);
 
                 if (angular.isUndefined(newHtml)) {