What potential issues could arise when using a wysiwyg editor in PHP?

One potential issue when using a wysiwyg editor in PHP is the possibility of allowing users to input malicious code, such as JavaScript, which could lead to security vulnerabilities like cross-site scripting (XSS) attacks. To prevent this, you can sanitize user input before displaying it on the page by using functions like strip_tags() or htmlspecialchars().

// Sanitize user input before displaying it
$user_input = "<script>alert('XSS attack!')</script>";
$sanitized_input = htmlspecialchars($user_input);

echo $sanitized_input;