自己解決しました。
“WordPress HTTPS”の使用を中止して、
自前の関数でヘッダ・フッタ内のファイルパスを全て相対パスに変換の上、
httpsでフォームにアクセスする事で、
普通に、完了画面まで行けました。
でも、いずれにせよ”WordPress HTTPS”と併用出来るか、
他の簡単な方法がわかると大変有り難いです。
宜しくお願い致します。
As a temporally solution,
I found a plugin “WP-Facebook applications” and started using it.
It’s working OK, but still functionally your plugin is much better.
So I still wait for any clue to solve my problem.
I add a bit more details of my situation.
I also tried “Reveal Tab Setup”.
Separating before/after-cliking-like contents into 2 post
and setting them as “Reveal Tab” pair,
Then “demo if page liked” link shows after-cliking-like contents
on the both server.
So on the new server,
Inside the WP, It works fine,
but inside the facebook App, It works strange.
On the old server, it works fine even inside the App.
Is there any clue to solve the situation?
