Pop-up login

How to enable pop-up login, instead of inline login ?

You can use any popup plugin and use social login shortcode to display login icons in popup.
Drop us an email at support[at]heateor[dot]com, if you want us to help you implement this.

Why it is not using for App Secret ( insecure) ? This is insecure as described by facebook.

Our plugin uses Javascript SDK for Facebook authentication which doesn’t require secret key. There is nothing insecure in it. Don’t you think if it would be insecure, Facebook would not have included it in their documentation?

I am not asking for adding modal login. I know, I can use the [shortcode] in modal to make that.

What I am asking for, this screen, https://fbcdn-dragon-a.akamaihd.net/hphotos-ak-xpa1/t39.2178-6/851546_620507588026124_290281089_n.png

This screen appears when a user logs in first time using Social Login. You can upload your app logo in Icons section at App details page in your Facebook app settings.

Yes, this screen should appears only for the first time. But I am not seeing this for the first time also. Its not asking for permission from user, for the first time.

It is not possible for screen to not appear first time. You might have logged in before, using that Facebook account from that app.
You would like to try Facebook login from another Facebook account.