What steps can be taken to troubleshoot and resolve discrepancies in how special characters are handled and displayed in different browsers when using PHP to interact with a MySQL database?

Special characters handling issues in PHP and MySQL can be resolved by ensuring that the character encoding is consistent across both the database and the PHP script. This can be achieved by setting the appropriate character set and collation in both the MySQL database and the PHP connection. Additionally, using functions like htmlspecialchars() and htmlentities() in PHP can help sanitize and properly display special characters in different browsers.

// Set character set and collation in MySQL connection
$mysqli = new mysqli("localhost", "username", "password", "database");
$mysqli->set_charset("utf8");

// Set character encoding in PHP script
header('Content-Type: text/html; charset=utf-8');

// Sanitize and display special characters
$text = "Special characters: <>&";
echo htmlspecialchars($text, ENT_QUOTES, 'UTF-8');