What potential issues can arise when using session variables in PHP, especially when it comes to cross-browser compatibility like in the case of IE 8?

When using session variables in PHP, one potential issue that can arise is with cross-browser compatibility, especially in older browsers like IE 8. This is because IE 8 has limitations with handling cookies, which are often used to store session IDs. To solve this issue, you can use session_start() with session_regenerate_id() to ensure a new session ID is generated for each request, bypassing the cookie limitations of IE 8.

session_start();
session_regenerate_id();