What are common issues faced when trying to disable the browser's password save prompt in PHP forms?

Common issues faced when trying to disable the browser's password save prompt in PHP forms include browsers overriding the autocomplete attribute, inconsistent browser support, and the need for additional JavaScript or CSS hacks to fully disable the prompt.

<form method="post" action="submit.php">
    <input type="text" name="username" autocomplete="off">
    <input type="password" name="password" autocomplete="new-password">
    <button type="submit">Submit</button>
</form>