diff --git a/app/capabilities.js b/app/capabilities.js
index 1603a002..1d6441d8 100644
--- a/app/capabilities.js
+++ b/app/capabilities.js
@@ -8,6 +8,7 @@ async function checkCrypto() {
       true,
       ['encrypt', 'decrypt']
     );
+    await crypto.subtle.exportKey('raw', key);
     await crypto.subtle.encrypt(
       {
         name: 'AES-GCM',