diff --git a/scripts/postbuild.js b/scripts/postbuild.js
index c992884b..6372bd65 100644
--- a/scripts/postbuild.js
+++ b/scripts/postbuild.js
@@ -2,7 +2,7 @@ require('dotenv').config();
 const sendTelemetry = require('./telemetry');
 
 async function run() {
-  if (!process.env.TELEMETRY_DISABLE) {
+  if (!process.env.DISABLE_TELEMETRY) {
     await sendTelemetry();
   }
 }
diff --git a/tracker/index.js b/tracker/index.js
index 312632d9..a5012b71 100644
--- a/tracker/index.js
+++ b/tracker/index.js
@@ -48,7 +48,7 @@ import { removeTrailingSlash } from '../lib/url';
   const post = (url, data, callback) => {
     const req = new XMLHttpRequest();
     req.open('POST', url, true);
-    req.setRequestHeader('Content-Type', 'text/plain');
+    req.setRequestHeader('Content-Type', 'application/json');
 
     req.onreadystatechange = () => {
       if (req.readyState === 4) {