diff --git a/content-security-policy/inheritance/document-write-iframe.html b/content-security-policy/inheritance/document-write-iframe.html
index a84e3a37031280..d6ad88ddc93df4 100644
--- a/content-security-policy/inheritance/document-write-iframe.html
+++ b/content-security-policy/inheritance/document-write-iframe.html
@@ -3,67 +3,63 @@
-
+
document.open() does not change Content Security Policies
+ promise_test(async () => {
+ let iframe = document.createElement('iframe');
+ document.body.appendChild(iframe);
-
-
+ let msg = message_from(iframe.contentWindow);
+ let doc = iframe.contentWindow.document;
+ doc.open();
+ doc.write("" + documentBody(false) + "");
+ doc.close();
+ assert_equals(await msg, "blocked");
+ }, "document.open() keeps inherited CSPs on empty iframe.");
-
-
+ promise_test(async () => {
+ let iframe = document.createElement('iframe');
+ let loaded = new Promise(resolve => iframe.onload = resolve);
+ iframe.src = "/common/blank.html";
+ document.body.appendChild(iframe);
+ await loaded;
-
-
-