diff --git a/ext/fg/js/popup.js b/ext/fg/js/popup.js
index 4ec34249..11b25d8f 100644
--- a/ext/fg/js/popup.js
+++ b/ext/fg/js/popup.js
@@ -59,7 +59,10 @@ class Popup {
 
     setContent(content) {
         if (this.popup !== null) {
-            this.popup.srcdoc = content;
+            const doc = this.popup.contentDocument;
+            doc.open();
+            doc.write(content);
+            doc.close();
         }
     }