diff --git a/dom/webbrowserpersist/WebBrowserPersistLocalDocument.cpp b/dom/webbrowserpersist/WebBrowserPersistLocalDocument.cpp
index 0495e5e4add9..ab0a5dc1c7cb 100644
--- a/dom/webbrowserpersist/WebBrowserPersistLocalDocument.cpp
+++ b/dom/webbrowserpersist/WebBrowserPersistLocalDocument.cpp
@@ -79,6 +79,12 @@ WebBrowserPersistLocalDocument::GetPersistFlags(uint32_t* aFlags) {
   return NS_OK;
 }
 
+NS_IMETHODIMP
+WebBrowserPersistLocalDocument::GetIsClosed(bool* aIsClosed) {
+  *aIsClosed = false;
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 WebBrowserPersistLocalDocument::GetIsPrivate(bool* aIsPrivate) {
   nsCOMPtr<nsILoadContext> privacyContext = mDocument->GetLoadContext();
diff --git a/dom/webbrowserpersist/WebBrowserPersistRemoteDocument.cpp b/dom/webbrowserpersist/WebBrowserPersistRemoteDocument.cpp
index 57de9308d065..bf274e56d27b 100644
--- a/dom/webbrowserpersist/WebBrowserPersistRemoteDocument.cpp
+++ b/dom/webbrowserpersist/WebBrowserPersistRemoteDocument.cpp
@@ -41,6 +41,12 @@ WebBrowserPersistRemoteDocument::~WebBrowserPersistRemoteDocument() {
 
 void WebBrowserPersistRemoteDocument::ActorDestroy(void) { mActor = nullptr; }
 
+NS_IMETHODIMP
+WebBrowserPersistRemoteDocument::GetIsClosed(bool* aIsClosed) {
+  *aIsClosed = !mActor;
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 WebBrowserPersistRemoteDocument::GetIsPrivate(bool* aIsPrivate) {
   *aIsPrivate = mAttrs.isPrivate();
diff --git a/dom/webbrowserpersist/nsIWebBrowserPersistDocument.idl b/dom/webbrowserpersist/nsIWebBrowserPersistDocument.idl
index 694783259772..24925e2fde1f 100644
--- a/dom/webbrowserpersist/nsIWebBrowserPersistDocument.idl
+++ b/dom/webbrowserpersist/nsIWebBrowserPersistDocument.idl
@@ -59,6 +59,7 @@ interface nsIWebBrowserPersistURIMap : nsISupports
 [scriptable, builtinclass, uuid(74aa4918-5d15-46b6-9ccf-74f9696d721d)]
 interface nsIWebBrowserPersistDocument : nsISupports
 {
+  readonly attribute boolean isClosed;
   readonly attribute boolean isPrivate;
   readonly attribute AUTF8String documentURI;
   readonly attribute AUTF8String baseURI;
diff --git a/dom/webbrowserpersist/nsWebBrowserPersist.cpp b/dom/webbrowserpersist/nsWebBrowserPersist.cpp
index ee669bd26258..7e143e230742 100644
--- a/dom/webbrowserpersist/nsWebBrowserPersist.cpp
+++ b/dom/webbrowserpersist/nsWebBrowserPersist.cpp
@@ -508,10 +508,13 @@ NS_IMETHODIMP nsWebBrowserPersist::SaveDocument(nsISupports* aDocument,
       rv = NS_ERROR_NO_INTERFACE;
     }
   }
-  if (doc) {
+
+  bool closed = false;
+  if (doc && NS_SUCCEEDED(doc->GetIsClosed(&closed)) && !closed) {
     rv = SaveDocumentInternal(doc, fileAsURI, datapathAsURI);
   }
-  if (NS_FAILED(rv)) {
+
+  if (NS_FAILED(rv) || closed) {
     SendErrorStatusChange(true, rv, nullptr, mURI);
     EndDownload(rv);
   }
diff --git a/toolkit/components/windowcreator/test/browser.ini b/toolkit/components/windowcreator/test/browser.ini
index 3bbad0771bbd..5e24f9cba33d 100644
--- a/toolkit/components/windowcreator/test/browser.ini
+++ b/toolkit/components/windowcreator/test/browser.ini
@@ -1,6 +1,4 @@
 [browser_bug1204626.js]
-fail-if = fission && !debug
-skip-if = fission && os == 'linux' && debug
 support-files =
   bug1204626_doc0.html
   bug1204626_doc1.html