diff --git a/src/common/contentScriptsUtils.js b/src/common/contentScriptsUtils.js
index 00bc556..cb7a67d 100644
--- a/src/common/contentScriptsUtils.js
+++ b/src/common/contentScriptsUtils.js
@@ -13,5 +13,5 @@
 export function injectScript(scriptName) {
   var script = document.createElement('script');
   script.src = scriptName;
-  document.head.appendChild(script);
+  (document.head || document.documentElement).append(script);
 }
diff --git a/src/contentScripts/utilsCommon/protojs.js b/src/common/protojs.js
similarity index 100%
rename from src/contentScripts/utilsCommon/protojs.js
rename to src/common/protojs.js
diff --git a/src/common/xhrInterceptorUtils.js b/src/common/xhrInterceptorUtils.js
index 867c323..526296c 100644
--- a/src/common/xhrInterceptorUtils.js
+++ b/src/common/xhrInterceptorUtils.js
@@ -1,3 +1,5 @@
+import {correctArrayKeys} from '../common/protojs';
+
 import xhrInterceptors from './xhrInterceptors.json5';
 
 export {xhrInterceptors};
@@ -10,25 +12,30 @@
 }
 
 export function getResponseJSON(xhr) {
+  let response;
   if (xhr.responseType === 'arraybuffer') {
     var arrBuffer = xhr.response;
     if (!arrBuffer) {
       console.error('No array buffer.');
       return undefined;
     }
-    var byteArray = new Uint8Array(arrBuffer);
-    var dec = new TextDecoder('utf-8');
-    var rawResponse = dec.decode(byteArray);
-    return JSON.parse(rawResponse);
+    let byteArray = new Uint8Array(arrBuffer);
+    let dec = new TextDecoder('utf-8');
+    let rawResponse = dec.decode(byteArray);
+    response = JSON.parse(rawResponse);
+  } else if (xhr.responseType === 'text' || xhr.responseType === '') {
+    response = JSON.parse(xhr.responseText);
+  } else if (xhr.responseType === 'json') {
+    response = xhr.response;
+  } else {
+    console.error(
+        'Unexpected responseType ' + xhr.responseType + '. Request url: ',
+        xhr.$TWPTRequestURL);
+    return undefined;
   }
-  if (xhr.responseType === 'text' || xhr.responseType === '')
-    return JSON.parse(xhr.responseText);
-  if (xhr.responseType === 'json') return xhr.response;
 
-  console.error(
-      'Unexpected responseType ' + xhr.responseType + '. Request url: ',
-      xhr.$TWPTRequestURL);
-  return undefined;
+  if (xhr.$isArrayProto) response = correctArrayKeys(response);
+  return response;
 }
 
 export function triggerEvent(eventName, body, id) {
diff --git a/src/contentScripts/communityConsole/start.js b/src/contentScripts/communityConsole/start.js
index d30a113..dce460b 100644
--- a/src/contentScripts/communityConsole/start.js
+++ b/src/contentScripts/communityConsole/start.js
@@ -7,6 +7,9 @@
 const SMEI_NESTED_REPLIES = 15;
 const SMEI_RCE_THREAD_INTEROP = 22;
 
+injectScript(chrome.runtime.getURL('xhrInterceptorInject.bundle.js'));
+injectScript(chrome.runtime.getURL('extraInfoInject.bundle.js'));
+
 getOptions(null).then(options => {
   /* IMPORTANT NOTE: Remember to change this when changing the "ifs" below!! */
   if (options.loaddrafts || options.interopthreadpage) {
@@ -59,7 +62,4 @@
         break;
     }
   }
-
-  injectScript(chrome.runtime.getURL('xhrInterceptorInject.bundle.js'));
-  injectScript(chrome.runtime.getURL('extraInfoInject.bundle.js'));
 });
diff --git a/src/contentScripts/publicProfile.js b/src/contentScripts/publicProfile.js
index 82e949e..693aa3f 100644
--- a/src/contentScripts/publicProfile.js
+++ b/src/contentScripts/publicProfile.js
@@ -1,7 +1,7 @@
 import {getOptions} from '../common/optionsUtils.js';
+import {correctArrayKeys} from '../common/protojs.js';
 
 import PerForumStatsSection from './communityConsole/utils/PerForumStatsSection.js';
-import {correctArrayKeys} from './utilsCommon/protojs.js';
 import {injectPreviousPostsLinksUnifiedProfile} from './utilsCommon/unifiedProfiles.js';
 
 const profileViewRegex = /var view ?= ?(.+\]);/;
diff --git a/src/injections/xhrInterceptor.js b/src/injections/xhrInterceptor.js
index 3ea4474..071daf5 100644
--- a/src/injections/xhrInterceptor.js
+++ b/src/injections/xhrInterceptor.js
@@ -1,11 +1,14 @@
+import {correctArrayKeys} from '../common/protojs';
 import * as utils from '../common/xhrInterceptorUtils.js';
 
-const originalOpen = XMLHttpRequest.prototype.open;
-const originalSend = XMLHttpRequest.prototype.send;
+const originalOpen = window.XMLHttpRequest.prototype.open;
+const originalSetRequestHeader =
+    window.XMLHttpRequest.prototype.setRequestHeader;
+const originalSend = window.XMLHttpRequest.prototype.send;
 
 let messageID = 0;
 
-XMLHttpRequest.prototype.open = function() {
+window.XMLHttpRequest.prototype.open = function() {
   this.$TWPTRequestURL = arguments[1] || location.href;
   this.$TWPTID = messageID++;
 
@@ -23,24 +26,39 @@
   originalOpen.apply(this, arguments);
 };
 
-XMLHttpRequest.prototype.send = function() {
+window.XMLHttpRequest.prototype.setRequestHeader = function() {
+  originalSetRequestHeader.apply(this, arguments);
+
+  let header = arguments[0];
+  let value = arguments[1];
+  if ('Content-Type'.localeCompare(
+          header, undefined, {sensitivity: 'accent'}) == 0)
+    this.$isArrayProto = (value == 'application/json+protobuf');
+};
+
+window.XMLHttpRequest.prototype.send = function() {
   originalSend.apply(this, arguments);
 
   let interceptors =
       utils.matchInterceptors('request', this.$TWPTRequestURL || location.href);
   if (interceptors.length > 0) {
-    var rawBody = arguments[0];
-    if (typeof (rawBody) !== 'object' ||
-        !(rawBody instanceof Object.getPrototypeOf(Uint8Array))) {
+    let rawBody = arguments[0];
+    let body;
+    if (typeof (rawBody) === 'object' &&
+        (rawBody instanceof Object.getPrototypeOf(Uint8Array))) {
+      let dec = new TextDecoder('utf-8');
+      body = dec.decode(rawBody);
+    } else if (typeof (rawBody) === 'string') {
+      body = rawBody;
+    } else {
       console.error(
-          'Request body is not Uint8Array, but ' + typeof (rawBody) + '.',
-          this.$TWPTRequestUrl);
+          'Unexpected type of request body (' + typeof (rawBody) + ').',
+          this.$TWPTRequestURL);
       return;
     }
 
-    var dec = new TextDecoder('utf-8');
-    var body = dec.decode(rawBody);
-    var JSONBody = JSON.parse(body);
+    let JSONBody = JSON.parse(body);
+    if (this.$isArrayProto) JSONBody = correctArrayKeys(JSONBody);
 
     interceptors.forEach(i => {
       utils.triggerEvent(i.eventName, JSONBody, this.$TWPTID);