Fix user fallback if user is not in initial batch for user_dropdown

#8224

includes/class-edd-html-elements.php

@@ -339,21 +339,21 @@ public function user_dropdown( $args = array() ) {
 			$options[0] = __( 'No users found', 'easy-digital-downloads' );
 		}
 
+		$selected = $args['selected'];
+		if ( ! is_array( $selected ) ) {
+			$selected = array( $selected );
+		}
 		// If a selected user has been specified, we need to ensure it's in the initial list of user displayed
-		if( ! empty( $args['selected'] ) ) {
-
-			if( ! array_key_exists( $args['selected'], $options ) ) {
-
-				$user = get_userdata( $args['selected'] );
-
-				if( $user ) {
-
-					$options[ absint( $args['selected'] ) ] = esc_html( $user->display_name );
+		if ( ! empty( $selected ) ) {
+			foreach ( $selected as $selected_user ) {
+				if ( ! array_key_exists( $selected_user, $options ) ) {
+					$user = get_userdata( $selected_user );
 
+					if ( $user ) {
+						$options[ absint( $args['selected'] ) ] = esc_html( $user->display_name );
+					}
 				}
-
 			}
-
 		}
 
 		$output = $this->select( array(