How Do I Use Error Handler in JavaScript in Browser?

Questions & Suggestions
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1

###How Do I Use Error Handler in JavaScript in Browser?

I seem to be missing something. When I use a try / catch section in a ExecuteJavaScript in Chrome Action, it does NOT catch any errors.
When I use the same script in a Execute JavaScript for Automation (JXA) script, it DOES catch the errors.

###Example Results
####JavaScript in Chrome

####JXA

###JavaScript Used in Both

'use strict';

var scriptResults = "TBD";

try {
  scriptResults = "JS Results: " + document.titleBAD;
  myUndefinedVar = "should fail";
  
}
catch (oErr) {
  scriptResults = "JS ERROR: " + oErr.message;
}
scriptResults;


###MACRO:   [JS] TEST JavaScript in Chrome

~~~ VER: 1.0    2017-04-22 ~~~

####DOWNLOAD:
<a class="attachment" href="/uploads/default/original/2X/7/7fc4aa224f2d0a48106ddfb9408ba77efb4823fe.kmmacros">[JS] TEST JavaScript in Chrome.kmmacros</a> (3.0 KB)

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<img src="/uploads/default/original/2X/1/18d52d8dedb7d1f74c184fc71ffeb25dc40ed2f6.png" width="566" height="991">
2

###Problem Resolved (my bad)

OK, I missed something basic: A reference to an unknown DOM element/attribute/property simply returns a typeof of "undefined". It does NOT throw an error.

This script DOES invoke the try / catch error handler when a real error occurs, like referencing an undefined variable (when using 'use strict').

'use strict';

var scriptResults = "TBD";

try {
  scriptResults = someUnknownVar;  //document.titleBAD;

  if (typeof scriptResults === 'undefined') throw new Error("JS result was 'undefined', most likely due referencing an unknow DOM element/attribute/property.");

  myUndefinedVar = "should fail";
  
}
catch (oErr) {
  scriptResults = "JS ERROR: " + oErr.message;
}

scriptResults;

###Example Results