Google's search suggest XHR requests

Question

I went to google, and had my firebug open. I started typing "in", and then checked the "NET" tab of Firebug, and a couple of new GET requests had been sent to fetch the list of search autocomplete suggestions.

Like:

GET http://clients1.google.com/complete/search?hl=en&client=hp&expIds=17259,17315,23628,24549,26637,26761,26849,26869,27386,27404&q=i&cp=1

But they were classified under the "JS" section, rather than as a "XHR" - why is this? Isn't google making an AJAX GET request behind the scene?

Answer 1

This is almost certainly a JSONP request, used to get around cross-domain restrictions on XHRs. Essentially, they are dynamically inserting <script /> tags into their page, and that's why it shows up under JS in Firebug.