How can I use browser developer tools to diagnose the "FirebaseError: reCAPTCHA placeholder element must be an element or id" error?

Use the browser's developer tools (e.g., Chrome DevTools): 1. Inspect the HTML to confirm the reCAPTCHA container element exists and has the correct ID. 2. Use the JavaScript console to check the value of `document.getElementById('your-recaptcha-id')` (replace 'your-recaptcha-id' with your actual ID) to ensure it returns an HTML element and not `null`. 3. Step through your JavaScript code to see exactly when Firebase is trying to initialize reCAPTCHA and whether the container element is present at that time.