diff --git a/docshell/base/nsDSURIContentListener.cpp b/docshell/base/nsDSURIContentListener.cpp
index 55cf7d5118..7aa3a5d14d 100644
--- a/docshell/base/nsDSURIContentListener.cpp
+++ b/docshell/base/nsDSURIContentListener.cpp
@@ -136,7 +136,7 @@ nsDSURIContentListener::DoContent(const nsACString& aContentType,
     mExistingJPEGRequest = baseChannel;
   }
 
-  if (rv == NS_ERROR_REMOTE_XUL) {
+  if (rv == NS_ERROR_REMOTE_XUL || rv == NS_ERROR_DOCSHELL_DYING) {
     aRequest->Cancel(rv);
     *aAbortProcess = true;
     return NS_OK;
diff --git a/docshell/base/nsDocShell.cpp b/docshell/base/nsDocShell.cpp
index d2e1af36b3..2ff5273d93 100644
--- a/docshell/base/nsDocShell.cpp
+++ b/docshell/base/nsDocShell.cpp
@@ -9040,6 +9040,12 @@ nsDocShell::CreateContentViewer(const nsACString& aContentType,
 {
   *aContentHandler = nullptr;
 
+  if (!mTreeOwner) {
+    // If we don't have a tree owner, then we're in the process of being
+    // destroyed. Rather than continue trying to load something, just give up.
+    return NS_ERROR_DOCSHELL_DYING;
+  }
+
   // Can we check the content type of the current content viewer
   // and reuse it without destroying it and re-creating it?
 
diff --git a/xpcom/base/ErrorList.h b/xpcom/base/ErrorList.h
index 192bc16e06..195b72998b 100644
--- a/xpcom/base/ErrorList.h
+++ b/xpcom/base/ErrorList.h
@@ -247,6 +247,9 @@
   ERROR(NS_ERROR_REMOTE_XUL,           FAILURE(75)),
   /* The request resulted in an error page being displayed. */
   ERROR(NS_ERROR_LOAD_SHOWED_ERRORPAGE, FAILURE(77)),
+  /* The request occurred in docshell that lacks a treeowner, so it is
+   * probably in the process of being torn down. */
+  ERROR(NS_ERROR_DOCSHELL_DYING,       FAILURE(78)),
 
 
   /* FTP specific error codes: */