Browser monitors: window.dispatchEvent and window.addEventListener functions in application code

nandini_balakri — Thu, 14 May 2026 13:57:58 GMT

Summary

Chrome Manifest V3 (MV3), the latest iteration of the Chrome extension platform, introduces stricter execution and security constraints that can affect browser monitoring behavior.

One known consequence of MV3 is unexpected data loss or monitor failures when application code overrides core browser event APIs such as:

window.dispatchEvent
window.addEventListener

Problem

When core browser event API functions are overridden, Dynatrace Browser Monitors may exhibit the following issues:

Missing resources or actions in waterfall data
Missing or incomplete JavaScript event results
Browser monitor execution failures

This behavior affects Browser Monitors run using older ActiveGates versions, <1.267.

How to Troubleshoot MV3‑Related Browser Monitor Issues

If you observe browser monitor anomalies that may be related to overridden event listeners, follow these steps:

Verify your ActiveGate version
Ensure you are running ActiveGate version 1.267 or later.
Earlier versions may not fully support Chrome MV3 behavior.
Update and retest your browser monitors
After upgrading ActiveGate, rerun the affected monitors to confirm whether the issue is resolved.

What's Next

Contact Dynatrace Support if issues persist
If problems continue after upgrading, contact Dynatrace Support and provide a link to the monitor, along with details of the troubleshooting steps you have already completed.

article Browser monitors: window.dispatchEvent and window.addEventListener functions in application code in Troubleshooting

Browser monitors: window.dispatchEvent and window.addEventListener functions in application code

Summary

Problem

How to Troubleshoot MV3‑Related Browser Monitor Issues

What's Next

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