diff --git a/view/js/dropzone-factory.js b/view/js/dropzone-factory.js
index 6039e11e4f..dcc0468cb2 100644
--- a/view/js/dropzone-factory.js
+++ b/view/js/dropzone-factory.js
@@ -35,7 +35,7 @@ var DzFactory = function (max_imagesize) {
 					if (targetTextarea.setRangeText) {
 						//if setRangeText function is supported by current browser
 						let u = "[upload-" + file.name + "]";
-						targetTextarea.setRangeText(serverResponse, targetTextarea.value.indexOf(u), targetTextarea.value.indexOf(u)+u.length, "end");
+						targetTextarea.setRangeText(serverResponse, targetTextarea.value.indexOf(u), targetTextarea.value.indexOf(u) + u.length, "end");
 					} else {
 						targetTextarea.focus();
 						document.execCommand('insertText', false /*no UI*/, serverResponse);