FB doesn't seem to respect ACCEPT headers sent to /feeds/page.php. See below example:
GET /feeds/page.php?id=10036618151&format=rss20 HTTP/1.1
Connection: Keep-Alive
**Accept: text/xml,application/xml**
Accept-Language: en-us
User-Agent: Mozilla/4.0 (compatible; Win32; WinHttp.WinHttpRequest.5)
Host: www.facebook.com
HTTP/1.1 200 OK
Cache-Control: private, no-cache, no-store, must-revalidate
**Content-type: application/rss+xml**
Expires: Sat, 01 Jan 2000 00:00:00 GMT
Last-Modified: Wed, 08 Feb 2012 10:05:49 -0800
P3P: CP="Facebook does not have a P3P policy. Learn why here: http://fb.me/p3p"
Pragma: no-cache
X-Content-Type-Options: nosniff
X-Frame-Options: DENY
Set-Cookie: datr=-vIzT4cxw52hjjqTfrpQkNYX; expires=Sat, 08-Feb-2014 16:23:22 GMT;path=/; domain=.facebook.com; httponly
X-FB-Debug: qx/SiyRZDiVPm4wfiKVj37HImPoKM+DVAsO4oKSbSr0=
X-Cnection: close
Date: Thu, 09 Feb 2012 16:23:22 GMT
Content-Length: 41236
I cannot seem to find a way to post a new bug report on http://developers.facebook.com/bugs, as I don't have the "Create" (nor the "Subscribe") buttons as described here http://developers.facebook.com/blog/post/559/
I have read that there are a fair few FB developers involved with this site, and was hoping that someone could shed some light on what I might be doing wrong / how to request FB changes the code to respect my request, or HTTP406 me.
If you go to http://developers.facebook.com/bugs and click on the Created link you will see a create button on the top right of the page. Or you can just go to: http://developers.facebook.com/bugs/create
I'm not seeing the Create button that other people are seeing (tried Chrome, FF & Safari), but if you type something into the "Search Bugs" field here, you'll see a "Create a new bug report" link as the last option. Not the most intuitive...
来源：https://stackoverflow.com/questions/9234386/how-to-submit-a-bug-report-to-facebook