Fix issue in the user provider

Author: aristath

classes/suggested-tasks/providers/class-user.php

@@ -112,6 +112,11 @@ public function modify_task_details_for_user_tasks_rest_format( $tasks, $args )
 
 		// Loop through all tasks in the flat array.
 		foreach ( $tasks as $key => $task ) {
+			// Only process user provider tasks.
+			if ( ! isset( $task['prpl_provider']->slug ) || $task['prpl_provider']->slug !== self::PROVIDER_ID ) {
+				continue;
+			}
+
 			if ( \in_array( $task['id'], $modified_tasks, true ) ) {
 				continue;
 			}