Index: src/wp-admin/includes/class-wp-ms-users-list-table.php
===================================================================
--- src/wp-admin/includes/class-wp-ms-users-list-table.php	(revision 42215)
+++ src/wp-admin/includes/class-wp-ms-users-list-table.php	(working copy)
@@ -266,6 +266,10 @@
 	public function column_name( $user ) {
 		if ( $user->first_name && $user->last_name ) {
 			echo "$user->first_name $user->last_name";
+		} else if ( !empty($user->first_name) ) {
+			echo "$user->first_name";
+		} else if ( !empty($user->last_name) ) {
+			echo "$user->last_name";
 		} else {
 			echo '<span aria-hidden="true">&#8212;</span><span class="screen-reader-text">' . _x( 'Unknown', 'name' ) . '</span>';
 		}
Index: src/wp-admin/includes/class-wp-users-list-table.php
===================================================================
--- src/wp-admin/includes/class-wp-users-list-table.php	(revision 42215)
+++ src/wp-admin/includes/class-wp-users-list-table.php	(working copy)
@@ -488,7 +488,14 @@
 					case 'name':
 						if ( $user_object->first_name && $user_object->last_name ) {
 							$r .= "$user_object->first_name $user_object->last_name";
-						} else {
+						} 
+						else if ( !empty($user_object->first_name) ) {
+							$r .= "$user_object->first_name";
+						} 
+						else if ( !empty($user_object->last_name) ) {
+							$r .= "$user_object->last_name";
+						} 
+						else {
 							$r .= '<span aria-hidden="true">&#8212;</span><span class="screen-reader-text">' . _x( 'Unknown', 'name' ) . '</span>';
 						}
 						break;