ajax - How does Facebook's Chat Window Remains open and in the same place When you navigate through pages

Question

How does Facebook's Chat Window Remains open and in the same place When you navigate through pages

Please before you answer:

1-I'm aware of Ajax very well and the current implementation in Facebook is not normal Ajax like it used to be in the past.

2-The URL of the page changes completely not the Hash part, and the whole page reloads but not the Chat window or panel.

I Found that the URL changes through this JS Part:

history.pushState({},"New Title Goes Here","http://facebook.com/Something");

But what about the data itself how doesn't it come ? the Network->XHR in Firebug or Chrome displays nothing in the XHR. so I guess it's not Ajax.

Answer 1

对我来说看起来像很多ajax。

他们在重新加载聊天窗口时是有选择性的。即：如果您转到帐户设置和其他较少访问的页面。

对于聊天窗口本身的加载，我相当肯定他们使用长轮询（彗星）。