Chrome extension: webRequest.onBeforeSendHeaders behaves strange

Question

I am trying to add a \"Referer\"-HTTP-Header to certain AJAX requests in my Chrome extension. You can\'t change it directly in the AJAX request so I tried to change it using

Answer 1

The reason you can't set the Referrer header when you don't have a blocking request is that the request has potentially already gone out - you are being notified asynchronously, and cannot change anything about the request.

To change headers, I use this code:

function mod_headers(header_array,p_name,p_value) {
     var did_set = false;                                                                                      
     for(var i in header_array) {                                                                                                   
         var header = header_array[i];                                                                                              
         var name = header.name;                                                                                                    
         var value = header.value;                                                                                                  

         // If the header is already present, change it:
         if(name == p_name) {
             header.value = p_value;
             did_set = true;
         }                                                                                                         
     }
     // if it is not, add it:
     if(!did_set) { header_array.push( { name : p_name , value : p_value } ); }                                                                                                                       
 }