dotproto/LICENSE

## content.js
console.log('content script – start body');

function injectScript(parent)  {
  console.log('injected script - start body')

  const script = document.createElement('script');
  script.textContent = `console.log('injected script'); window.GlobalClass = function() {};`;
  parent.appendChild(script);
}

// Options for the observer (which mutations to observe)
var config = { attributes: false, childList: true, subtree: false };

// Callback function to execute when mutations are observed
var callback = function(mutationsList, observer) {
  var targetNodeFound = false;
  for(var mutation of mutationsList) {
    console.log('A child node has been added or removed.', mutation);
    for (var node of mutation.addedNodes) {
      if (node.nodeName === 'HEAD') {
        injectScript(node);
      }
    }
  }
};

// Create an observer instance linked to the callback function
var observer = new MutationObserver(callback);

// Start observing the target node for configured mutations
observer.observe(document.documentElement, config);

## index.html
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Document</title>
</head>
<body>
  This is a test
  <script>
    console.log('inline page script - start body');
    let a = new GlobalClass();
  </script>
</body>
</html>

## LICENSE
Copyright 2019 Google LLC

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

## manifest.json
{
  "name": "Content script loader test",
  "version": "1.0.0",
  "manifest_version": 2,
  "content_scripts": [
    {
      "matches": ["file:///*"],
      "js": ["content.js"],
      "run_at": "document_start"
    }
  ],
  "web_accessible_resources": [
    "inject.js"
  ]
}
	console.log('content script – start body');

	function injectScript(parent) {
	console.log('injected script - start body')

	const script = document.createElement('script');
	script.textContent = `console.log('injected script'); window.GlobalClass = function() {};`;
	parent.appendChild(script);
	}

	// Options for the observer (which mutations to observe)
	var config = { attributes: false, childList: true, subtree: false };

	// Callback function to execute when mutations are observed
	var callback = function(mutationsList, observer) {
	var targetNodeFound = false;
	for(var mutation of mutationsList) {
	console.log('A child node has been added or removed.', mutation);
	for (var node of mutation.addedNodes) {
	if (node.nodeName === 'HEAD') {
	injectScript(node);
	}
	}
	}
	};

	// Create an observer instance linked to the callback function
	var observer = new MutationObserver(callback);

	// Start observing the target node for configured mutations
	observer.observe(document.documentElement, config);
	<!DOCTYPE html>
	<html lang="en">
	<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<meta http-equiv="X-UA-Compatible" content="ie=edge">
	<title>Document</title>
	</head>
	<body>
	This is a test
	<script>
	console.log('inline page script - start body');
	let a = new GlobalClass();
	</script>
	</body>
	</html>
	Copyright 2019 Google LLC

	Licensed under the Apache License, Version 2.0 (the "License");
	you may not use this file except in compliance with the License.
	You may obtain a copy of the License at

	https://www.apache.org/licenses/LICENSE-2.0

	Unless required by applicable law or agreed to in writing, software
	distributed under the License is distributed on an "AS IS" BASIS,
	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	See the License for the specific language governing permissions and
	limitations under the License.
	{
	"name": "Content script loader test",
	"version": "1.0.0",
	"manifest_version": 2,
	"content_scripts": [
	{
	"matches": ["file:///*"],
	"js": ["content.js"],
	"run_at": "document_start"
	}
	],
	"web_accessible_resources": [
	"inject.js"
	]
	}