What are common pitfalls when trying to manipulate window size in PHP?

Common pitfalls when trying to manipulate window size in PHP include not using the correct functions or not properly handling errors. To solve this, make sure to use the appropriate functions like `header()` to set the content type and `echo` to output the content. Additionally, always check for errors and handle them gracefully to prevent unexpected behavior.

<?php
// Set the content type and output the content
header('Content-Type: text/html');
echo '<script>window.resizeTo(800, 600);</script>';
?>