Full-Page monitor for https page is not working as expected

Products

• CA App Synthetic Monitor

Issue/Introduction

We have create a full-page monitor for URL https://hostname.example.com/

The monitor fails to open the page correctly, and the following errors are showing up:

SyntaxError: Unexpected keyword 'const'. Const declarations are not supported in strict mode.
https://example.com/resources/<path>/filename.js

SyntaxError: Unexpected use of reserved word 'let' in strict mode
https://example.com/resources/<path>/filename.js

 

We are unable to find these errors in the chrome and/or FF when we review the details via Developer Tools. When we review the two JavaScripts that are encountering SyntaxError, we do see that both 'const' and 'let' are being used in the scripts.

Environment

Release : SAAS

Component : APP SYNTHETIC MONITOR ENVIRONMENTAL

Resolution

This error is only present when using the old webkit-based Full-Page monitor. We are replacing it with a new implementation based on Chromium, but this is disabled by default on public stations.

To use the new Full-Page monitor, turn on the option 'Use the new FPM agent' in the monitor's advanced settings. With the new monitor the JavaScript errors are not present.