重新启动是因为Facebook在不同的php会话中回调，并且无法从调用者会话中访问配置信息。
看看Endpoint.php
如果（！$ storage-> config（CONFIG））...
原因是因为我在我的网站中使用127.0.0.1但是return_uri是与localhost因为Facebook的限制。
PHP在这种情况下构建不同的会话。

The reasen is because Facebook callback in different php-session and cant access config info from caller session. Look at Endpoint.php if ( ! $storage->config( "CONFIG" ) ) ... The rason was because I use in my site with 127.0.0.1 but return_uri was with localhost because of Facebook restrictions. PHP builds different sessions in this case.