Handle the window.onerror Event

If any script on your monitored web pages, including library code, sets the JavaScript window.onerror event, add the following method to the page immediately after setting window.onerror:

<script>
ADRUM.listenForErrors()
</script>

The JavaScript Agent (adrum.js) sets window.onerror to listen for uncaught JavaScript errors. If this listener is overwritten, errors are not reported.

The agent invokes your original onerror handler.