1 files changed, 13 insertions, 0 deletions
diff --git a/layout/style/res/noframes.css b/layout/style/res/noframes.css
new file mode 100644
index 0000000000..4d1adfdc1f
--- /dev/null
+++ b/layout/style/res/noframes.css
@@ -0,0 +1,13 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* This sheet is added to the style set for documents with frames disabled */
+
+noframes {
+  display: block;
+}
+
+frame, frameset, iframe {
+  display: none !important;
+}