title: Firebase AppCheck - web app not working in debug mode
body: <p>I have setup Firebase AppCheck for my Web App and everything seemed to work fine. Now I would like to enable the debug mode when developing my app.</p>
  <p>I followed the instructions in the <a href="https://firebase.google.com/docs/app-check/web-debug-provider#localhost" rel="nofollow noreferrer">official documentation</a> but I keep getting random errors from the AppCheck module, and these prevent my app from accessing Firebase Storage:</p>
  <blockquote>
  <p>...at Backend FirebaseError: AppCheck: Fetch server returned an HTTP
  error status. HTTP status: 429. (appCheck/fetch-status-error).</p>
  </blockquote>
  <p>Following the doc, this is the way I set AppCheck in debug mode - this is ran before everything else:</p>
  <pre><code>if(window.location.hostname == &quot;localhost&quot;)
    self.FIREBASE_APPCHECK_DEBUG_TOKEN = true;
  </code></pre>
  <p>Again, when my app is not in debug mode it works just fine.</p>
  <p>Note 1: that I am not enforcing AppCheck via the console, and that 100% of the requests are displayed as &quot;Verified&quot;</p>
  <p><a href="https://i.stack.imgur.com/tjsgT.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/tjsgT.jpg" alt="enter image description here" /></a></p>
  <p>Note 2: googling for &quot;Firebase error 429&quot; shows many results referring to some quota being exceeded, something hardly possible for my dev environment (we are 2 devs and definitely not putting in any sort of load on the app)</p>