diff --git a/src/wp-admin/css/wp-admin.css b/src/wp-admin/css/wp-admin.css
index f274bcbb27..86a7efbdd3 100644
--- a/src/wp-admin/css/wp-admin.css
+++ b/src/wp-admin/css/wp-admin.css
@@ -6728,11 +6728,16 @@ body.theme-overlay-open {
 .theme-overlay .right:hover,
 .theme-overlay .left:hover {
 	background: #333;
+	color: #fff;
 }
 
-.theme-overlay .right:hover:before,
-.theme-overlay .left:hover:before {
-	color: #fff;
+.theme-overlay .left.disabled,
+.theme-overlay .right.disabled,
+.theme-overlay .left.disabled:hover,
+.theme-overlay .right.disabled:hover {
+	color: #ccc;
+	background: inherit;
+	cursor: inherit;
 }
 
 .theme-overlay .right:before,
diff --git a/src/wp-admin/js/theme.js b/src/wp-admin/js/theme.js
index 8039135fd7..b144157117 100644
--- a/src/wp-admin/js/theme.js
+++ b/src/wp-admin/js/theme.js
@@ -305,6 +305,14 @@ themes.view.Details = wp.Backbone.View.extend({
 				self.collapse();
 			}
 		});
+
+		// Disable Left/Right when at the start or end of the collection
+		if ( this.model.cid === this.model.collection.at(0).cid ) {
+			this.$el.find( '.left' ).addClass( 'disabled' );
+		}
+		if ( this.model.cid === this.model.collection.at( this.model.collection.length - 1 ).cid ) {
+			this.$el.find( '.right' ).addClass( 'disabled' );
+		}
 	},
 
 	// Performs the actions to effectively close