Untitled

<!DOCTYPE html>
<html lang="en">
<head></head>

<body>

<div id="txt_stage_1">_1_</div>
<div id="txt_stage_2">_2_</div>
<div id="txt_error">_no_error_</div>

<script>

	function initExample() {

		document.getElementById("txt_stage_1").innerText = "stage 1: passing?";

		console.log("passed stage 1"); // works even if devtools are closed in Edge/IE11.

		document.getElementById("txt_stage_1").innerText = "stage 1: passed: console.log: " + console.log;

		try {

			document.getElementById("txt_stage_2").innerText = "stage 2: passing?";

			var x = console.log;

			document.getElementById("txt_stage_2").innerText = "stage 2: passing? x: " + x;
			//var x = console.log.bind(this); // does not work, same TypeError.

			x('passed stage 2'); // only works if devtools are open in Edge/IE11.

			document.getElementById("txt_stage_2").innerText = "stage 2: passed: x: " + x;

		} catch (e) {

			// If devtools are not open a TypeError is thrown which hinders further execution
			// of the function that is calling that x(). So wrapping an anonymous function around x
			// will stop execution of the anonymous function, but the other code will continue to
			// work. If no wrapping function is provided then x is in the scope of the rest of the
			// module function and this script will stop execution when the TypeError is thrown.

			document.getElementById("txt_error").innerText = "stage 3 error: " + e;
		}
	}

	// IE11, closed devtools:
	// stage 1: passed: console.log:
	// function log() {
	// 	[native code]
	// }
	// stage 2: passing? x:
	// 	function log() {
	// 		[native code]
	// 	}
	// stage 3 error: TypeError: Ungültiges aufrufendes Objekt.

	// IE11, open devtools:
	// stage 1: passed: console.log: function __BROWSERTOOLS_CONSOLE_SAFEFUNC(){try{return n(arguments)}catch(i){t(i)}}
	// stage 2: passed: x: function __BROWSERTOOLS_CONSOLE_SAFEFUNC(){try{return n(arguments)}catch(i){t(i)}}
	// _no_error_

	// Edge, open devtools:
	// stage 1: passed: console.log: function __BROWSERTOOLS_CONSOLE_SAFEFUNC() { [native code] }
	// stage 2: passed: x: function __BROWSERTOOLS_CONSOLE_SAFEFUNC() { [native code] }
	// _no_error_

	// Edge, closed devtools:
	// stage 1: passed: console.log: function log() { [native code] }
	// stage 2: passing? x: function log() { [native code] }
	// stage 3 error: TypeError: Ungültiges aufrufendes Objekt.

	window.onload = initExample;

</script>

</body>

</html>