diff --git a/openslides/core/static/js/core/pdf.js b/openslides/core/static/js/core/pdf.js
index c56ee5be2..f4980aefe 100644
--- a/openslides/core/static/js/core/pdf.js
+++ b/openslides/core/static/js/core/pdf.js
@@ -410,7 +410,7 @@ angular.module('OpenSlidesApp.core.pdf', [])
                          */
                         extractLineNumbers = function(element) {
                             var foundLineNumbers = [];
-                            if (element.nodeName == 'SPAN' && element.getAttribute('class').indexOf('os-line-number') > -1) {
+                            if (element.nodeName == 'SPAN' && element.getAttribute('class') && element.getAttribute('class').indexOf('os-line-number') > -1) {
                                 foundLineNumbers.push(element.getAttribute('data-line-number'));
                                 element.parentNode.removeChild(element);
                             } else {
diff --git a/tests/karma/core/pdf.service.test.js b/tests/karma/core/pdf.service.test.js
index 2b4807257..c97671b80 100644
--- a/tests/karma/core/pdf.service.test.js
+++ b/tests/karma/core/pdf.service.test.js
@@ -158,6 +158,17 @@ describe('pdf', function () {
                 "margin": [0,10,0,0]
             }));
             expect(JSON.stringify(pdfmake[2])).toBe(emptyline);
-        })
+        });
+
+        it('does not break with non-line-break SPANs', function () {
+            var inHtml = "<ol><li>Test line 1<span>empty span</span></li></ol>",
+                numberedHtml = lineNumberingService.insertLineNumbers(inHtml, 80);
+
+            var instance = PdfMakeConverter.createInstance();
+            var pdfmake = instance.convertHTML(numberedHtml, 'outside');
+
+            // the actual result is's the point here; only that it doesn't throw an exception
+            expect(JSON.stringify(pdfmake[0])).toBe(emptyline);
+        });
     });
 });
\ No newline at end of file