tml_admin_add_extension_update_messages()

function tml_admin_add_extension_update_messages() {
    foreach ( tml_get_extensions() as $extension ) {
        add_action( 'in_plugin_update_message-' . $extension->get_basename(), 'tml_admin_extension_update_message', 10, 2 );
    }
}

View src/admin/extensions.php, line 296 on GitHub