diff --git a/phpBB/styles/prosilver/theme/common.css b/phpBB/styles/prosilver/theme/common.css
index f8f56a0020..96d965e987 100644
--- a/phpBB/styles/prosilver/theme/common.css
+++ b/phpBB/styles/prosilver/theme/common.css
@@ -1108,7 +1108,6 @@ form > p.post-notice strong {
 
 .dropdown-extended {
 	display: none;
-	width: 340px;
 	z-index: 1;
 }
 
@@ -1140,6 +1139,7 @@ form > p.post-notice strong {
 
 .dropdown-extended .dropdown-contents {
 	max-height: none;
+	max-width: 340px !important;
 	padding: 0;
 }
 
diff --git a/phpBB/styles/prosilver/theme/responsive.css b/phpBB/styles/prosilver/theme/responsive.css
index cea7656d7f..d921da62fb 100644
--- a/phpBB/styles/prosilver/theme/responsive.css
+++ b/phpBB/styles/prosilver/theme/responsive.css
@@ -190,8 +190,8 @@ ul.topiclist li.row dt a.subforum {
 ----------------------------------------*/
 @media only screen and (max-width: 350px), only screen and (max-device-width: 350px)
 {
-	.dropdown-extended {
-		width: 250px;
+	.dropdown-extended .dropdown-contents {
+		max-width: 300px !important;
 	}
 }