Fix member search filter with user_login field

core/um-filters-members.php

@@ -16,14 +16,23 @@
 		extract( $args );
 
 		$query = $ultimatemember->permalinks->get_query_array();
+		$arr_columns = array();
 
 		foreach( $ultimatemember->members->core_search_fields as $key ) {
 
 			if ( isset( $query[$key] ) && ! empty( $query[$key]  ) ) {
-				$query_args['search']         = '*' . trim($query[$key]) . '*';
+				$arr_columns[] = $key;
+				if( $key == 'user_login' ){
+					$query_args['search'] = trim($query[$key]);
+				}else{ 
+					$query_args['search'] = '*' . trim($query[$key]) . '*';
+				}
 			}
 		}
 
+		if( ! empty( $query_args ) ){
+			$query_args['search_columns'] = $arr_columns;
+		}
 		return $query_args;
 	}
 
@@ -301,7 +310,7 @@
 		} else {
 			$result['no_users'] = 0;
 		}
-
+   
 		return $result;
 	}