diff --git a/phpBB/adm/style/admin.css b/phpBB/adm/style/admin.css
index 77a2a794a3..900efca7b5 100644
--- a/phpBB/adm/style/admin.css
+++ b/phpBB/adm/style/admin.css
@@ -2317,6 +2317,8 @@ fieldset.permissions .permissions-switch {
 }
 
 .permissions-category ul {
+	display: flex;
+	flex-wrap: wrap;
 	margin: 0;
 	padding: 0;
 	list-style: none;
@@ -2567,6 +2569,10 @@ fieldset.permissions .permissions-switch {
 		margin: 0 !important;
 	}
 
+	.permissions-category ul {
+		display: block;
+	}
+
 	.permissions-category a,
 	.permissions-category a span.tabbg {
 		background: transparent none;