undefined is not an object (evaluating 'a.H')

This error has been appearing across many websites since June 2025, particularly affecting iOS devices running Safari, Chrome for iOS, or the Google App. The error originates from Google Translate’s JavaScript code when it attempts to access properties on undefined objects within its minified translation service.

The error appears as “undefined is not an object (evaluating ‘a.H’)” where ‘a.H’ represents minified property access in Google’s translation scripts. This error occurs within Google’s own code when their translation service encounters issues processing page content or initializing translation features.

Important: This error comes from Google Translate’s service, not your application code, and can be safely ignored in error monitoring.

The Problem

“undefined is not an object (evaluating ‘a.H’)” occurs when Google Translate’s JavaScript attempts to access properties on undefined objects within its minified code. The error manifests when Google’s translation service runs into issues while:

• Processing page content for translation
• Initializing translation widgets or overlays
• Handling language detection on iOS devices
• Managing translation state in mobile browsers

The error originates from Google’s translate scripts loaded from: https://translate.googleapis.com/_/translate_http/_/js/

The minified nature of Google’s code means property names like ‘a.H’ don’t provide meaningful debugging information - they represent obfuscated variable names in Google’s translation engine.

Key point: This error indicates issues within Google Translate’s service execution, not problems with your website’s code or functionality.

Understanding the Root Cause

“undefined is not an object (evaluating ‘a.H’)” stems from Google Translate service issues on iOS platforms:

1. Google Translate Service Execution

Primary cause: Google Translate’s JavaScript encounters undefined objects while processing page content or managing translation features on iOS devices.

How to identify: Errors originate from translate.googleapis.com domains in stack traces, particularly affecting iOS Safari, Chrome for iOS, and Google App users.

2. iOS-Specific Browser Behavior

iOS browsers may handle Google Translate’s JavaScript differently than desktop browsers, leading to timing issues or API availability problems.

How to identify: Error reports predominantly from iOS devices across different browsers (Safari, Chrome, Google App).

How to Fix “undefined is not an object (evaluating ‘a.H’)”

Quick Troubleshooting Checklist

• Recognize this as a Google Translate service issue, not your application error
• Configure error monitoring to ignore errors from translate.googleapis.com
• Check for “Jm@” function names in stack traces for older browsers
• Verify your website functions normally despite these errors
• Focus debugging efforts on actual application issues

Since this error originates from Google’s service, the solution is filtering it from monitoring:

Step 1: Configure TrackJS to Ignore Google Translate Errors

Set up ignore rules to filter out Google Translate service errors:

TrackJS Ignore Rule Configuration:

Option 1: Filter by stack trace (recommended)

• Stack trace contains: translate.googleapis.com

Option 2: Filter by function name (for older browsers)

• Stack trace contains: Jm@

These server-side ignore rules automatically filter out Google Translate errors without requiring any code changes.

Step 2: Verify Application Independence

Ensure your website functions correctly regardless of Google Translate errors:

Testing your application with Google Translate:

1. Visit your website in Safari on iOS (iPhone or iPad)
2. Set your device language to something different than your website’s language to trigger translation options
3. Tap the translate button (if it appears) or use the share menu to translate the page
4. Test all critical functionality while the page is being translated
5. Verify the application works normally despite any Google Translate errors appearing in monitoring

Alternatively, you can test Google Translate functionality by:

• Using Chrome’s built-in translate feature on mobile
• Testing through the Google App browser with auto-translation enabled
• Manually triggering translation on pages with foreign language content

Your application should function normally regardless of Google Translate service errors, since these errors occur within Google’s translation processing and don’t affect your website’s core functionality.

Step 3: Monitor Error Patterns

Track Google Translate error trends to understand their impact on your error monitoring signal-to-noise ratio. Error monitoring services like TrackJS can help identify if Google Translate errors are generating significant noise that obscures actual application issues.

While these errors should be filtered from alerting, monitoring their volume can help you understand the prevalence of translation service usage among your users.

When to Ignore This Error

“undefined is not an object (evaluating ‘a.H’)” should almost always be ignored because:

• Third-party service: Error originates from Google Translate, not your application
• No user impact: Translation service errors don’t affect core website functionality
• Outside your control: Cannot fix issues within Google’s translation service
• iOS platform specific: Represents platform-specific behavior in Google’s code

However, investigate if you notice:

• Correlation with actual issues: Google Translate errors coinciding with real application problems
• User complaints: Users reporting translation-related functionality problems
• Site integration issues: If your site specifically integrates with Google Translate widgets

Summary

“undefined is not an object (evaluating ‘a.H’)” is an error from Google Translate’s service that has been affecting iOS devices since June 2025. This error occurs within Google’s minified translation code and represents issues in their service execution, not problems with your website.

The appropriate response is filtering these errors from your monitoring system using filename matching (translate.googleapis.com) or function name patterns (Jm@) for older browsers. Focus your debugging efforts on actual application issues rather than third-party service errors.

Remember: Third-party service errors are a normal part of the web ecosystem where external services run code on your pages. The key is distinguishing between errors you can fix and noise from services outside your control.