diff --git a/webapp/src/main/webapp/themes/iph/js/collapsible_elements.js b/webapp/src/main/webapp/themes/iph/js/collapsible_elements.js
index ef2bad0b..d661b299 100644
--- a/webapp/src/main/webapp/themes/iph/js/collapsible_elements.js
+++ b/webapp/src/main/webapp/themes/iph/js/collapsible_elements.js
@@ -75,6 +75,9 @@ function switchExpand(inputID,elementsClass) {
 }
 function showDocumentCollapseButton(inputID){
 	var inputElement = document.getElementById(inputID);
+	if (inputElement === null){
+		return;
+	}
 	var collapseTextControl = inputElement.parentElement.querySelector('.collapseTextControl');
 	collapseTextControl.style.display = "inline";
 	var expandTextControl = inputElement.parentElement.querySelector('.expandTextControl');
@@ -83,6 +86,9 @@ function showDocumentCollapseButton(inputID){
 
 function showDocumentExpandButton(inputID){
 	var inputElement = document.getElementById(inputID);
+	if (inputElement === null){
+		return;
+	}
 	var collapseTextControl = inputElement.parentElement.querySelector('.collapseTextControl');
 	collapseTextControl.style.display = "none";
 	var expandTextControl = inputElement.parentElement.querySelector('.expandTextControl');