Firefox extension content script cannot request XMLHttpRequest

Question

According to the Firefox Content Script ,the XMLHttpRequset can be used.

I have tried both XMLHttpRequest and Api Fectch.It only responses with error message. I already disable CORS on the server.It still dosen't work.

I run Django local server on the computer.

This is the code:

function getWord(word){
   var req = new XMLHttpRequest();
   req.open("GET", "http://127.0.0.1:8000/api/${word}/",true);
   req.onload = function(){
      console.log("done");
   }
   req.onerror = function(){
      console.log("error : ",this.error);
   }
   req.send();

Console error:

error { target: XMLHttpRequest, isTrusted: true, lengthComputable: false, loaded: 0, total: 0, currentTarget: XMLHttpRequest, eventPhase: 2, bubbles: false, cancelable: false, defaultPrevented: false, … }

It work on other files(Not extension).

Answer 1

Problem solve

The problem is that I forgot to set the permission in the manifest.json.

https://developer.mozilla.org/en-US/Add-ons/WebExtensions/manifest.json/permissions