--- a/content/base/src/nsDocument.cpp
+++ b/content/base/src/nsDocument.cpp
@@ -9362,16 +9362,22 @@ nsDocument::GetTemplateContentsOwner()
                                     scriptObject, // aEventObject
                                     DocumentFlavorHTML);
     NS_ENSURE_SUCCESS(rv, nullptr);
 
     mTemplateContentsOwner = do_QueryInterface(domDocument);
     NS_ENSURE_TRUE(mTemplateContentsOwner, nullptr);
 
     mTemplateContentsOwner->SetScriptHandlingObject(scriptObject);
+
+    // Set |doc| as the template contents owner of itself so that
+    // |doc| is the template contents owner of template elements created
+    // by |doc|.
+    nsDocument* doc = static_cast<nsDocument*>(mTemplateContentsOwner.get());
+    doc->mTemplateContentsOwner = doc;
   }
 
   return mTemplateContentsOwner;
 }
 
 void
 nsDocument::RegisterHostObjectUri(const nsACString& aUri)
 {

--- a/content/html/content/src/HTMLTemplateElement.cpp
+++ b/content/html/content/src/HTMLTemplateElement.cpp
@@ -34,26 +34,18 @@ HTMLTemplateElement::HTMLTemplateElement
   : nsGenericHTMLElement(aNodeInfo)
 {
   SetHasWeirdParserInsertionMode();
 }
 
 nsresult
 HTMLTemplateElement::Init()
 {
-  nsIDocument* doc = OwnerDoc();
-  nsIDocument* contentsOwner = doc;
-
-  // Used to test if the document "has a browsing context".
-  nsCOMPtr<nsISupports> container = doc->GetContainer();
-  if (container) {
-    // GetTemplateContentsOwner lazily creates a document.
-    contentsOwner = doc->GetTemplateContentsOwner();
-    NS_ENSURE_TRUE(contentsOwner, NS_ERROR_UNEXPECTED);
-  }
+  nsIDocument* contentsOwner = OwnerDoc()->GetTemplateContentsOwner();
+  NS_ENSURE_TRUE(contentsOwner, NS_ERROR_UNEXPECTED);
 
   mContent = contentsOwner->CreateDocumentFragment();
   mContent->SetHost(this);
 
   return NS_OK;
 }
 
 HTMLTemplateElement::~HTMLTemplateElement()

--- a/dom/tests/mochitest/webcomponents/test_template.html
+++ b/dom/tests/mochitest/webcomponents/test_template.html
@@ -45,16 +45,24 @@ ok(!document.getElementById("insidetempl
 is(templateEl.childNodes.length, 0, "Template element should have no children.");
 is(templateEl.content.childNodes.length, 1, "Template content should have 1 child <div>.");
 
 // Make sure that template is owned by different document.
 ok(templateEl.content.ownerDocument != templateEl.ownerDocument, "Template should be in a different document because the current document has a browsing context.");
 var otherTemplateEl = document.getElementById("first");
 is(templateEl.content.ownerDocument, otherTemplateEl.content.ownerDocument, "Template contents within the same document should be owned by the same template contents owner.");
 
+var htmlDoc = document.implementation.createHTMLDocument();
+var otherDocTemplateEl = htmlDoc.createElement("template");
+isnot(otherDocTemplateEl.content.ownerDocument, htmlDoc, "Template content owner should be a new document.");
+
+var templateOwnerDoc = otherDocTemplateEl.content.ownerDocument;
+var docCreatedTemplateEl = templateOwnerDoc.createElement("template");
+is(docCreatedTemplateEl.content.ownerDocument, templateOwnerDoc, "Template content owner of template elements created by a template document should be the template document.");
+
 // Tests for XMLSerializer
 templateEl = document.getElementById("justtemplate");
 var serializer = new XMLSerializer();
 is(serializer.serializeToString(templateEl), '<template xmlns="http://www.w3.org/1999/xhtml" id="justtemplate"></template>', "XMLSerializer should serialize template element.");
 
 templateEl = document.getElementById("first");
 is(serializer.serializeToString(templateEl), '<template xmlns="http://www.w3.org/1999/xhtml" id="first">Hi<template>Bye</template></template>', "XMLSerializer should serialize template content.");