diff --git a/phpBB/styles/prosilver/theme/common.css b/phpBB/styles/prosilver/theme/common.css
index 19b0f65a2d..5dd5ecdb28 100644
--- a/phpBB/styles/prosilver/theme/common.css
+++ b/phpBB/styles/prosilver/theme/common.css
@@ -1173,6 +1173,12 @@ ul.linklist:after,
 	text-transform: none;
 }
 
+.dropdown-extended .header:after {
+	content: '';
+	display: table;
+	clear: both;
+}
+
 .dropdown-extended .footer {
 	text-align: center;
 	font-size: 1.1em;
diff --git a/phpBB/styles/subsilver2/theme/stylesheet.css b/phpBB/styles/subsilver2/theme/stylesheet.css
index 784643a5b9..8f0bbffdda 100644
--- a/phpBB/styles/subsilver2/theme/stylesheet.css
+++ b/phpBB/styles/subsilver2/theme/stylesheet.css
@@ -1224,6 +1224,12 @@ a.imageset {
 	text-transform: none;
 }
 
+#notification_list .header:after {
+	content: '';
+	display: table;
+	clear: both;
+}
+
 #notification_list .footer {
 	text-align: center;
 	font-size: 1.2em;