mweststrate/index.html

## index.html
<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8">
    <title>Hello World!</title>
    <link rel="stylesheet" type="text/css" href="./styles.css">
  </head>
  <body>
    <h1>Hello World!</h1>
    <!-- All of the Node.js APIs are available in this renderer process. -->
    We are using Node.js <script>document.write(process.versions.node)</script>,
    Chromium <script>document.write(process.versions.chrome)</script>,
    and Electron <script>document.write(process.versions.electron)</script>.

    <button id="test">Go</button>
    <script>
      // You can also require other files to run in this process
      require('./renderer.js')
    </script>
  </body>
</html>

## main.js
// Modules to control application life and create native browser window
const {app, BrowserWindow} = require('electron')

function createWindow () {
  // Create the browser window.
  const mainWindow = new BrowserWindow({
    width: 800,
    height: 600,
    webPreferences: {
      worldSafeExecuteJavaScript: false,
      contextIsolation: false,
      nodeIntegration: true
    }
  })

  // and load the index.html of the app.
  mainWindow.loadFile('index.html')

  // Open the DevTools.
  // mainWindow.webContents.openDevTools()
}

// This method will be called when Electron has finished
// initialization and is ready to create browser windows.
// Some APIs can only be used after this event occurs.
app.whenReady().then(createWindow)

// Quit when all windows are closed, except on macOS. There, it's common
// for applications and their menu bar to stay active until the user quits
// explicitly with Cmd + Q.
app.on('window-all-closed', function () {
  if (process.platform !== 'darwin') {
    app.quit()
  }
})

app.on('activate', function () {
  // On OS X it's common to re-create a window in the app when the
  // dock icon is clicked and there are no other windows open.
  if (BrowserWindow.getAllWindows().length === 0) {
    createWindow()
  }
})

// In this file you can include the rest of your app's specific main process
// code. You can also put them in separate files and require them here.

## preload.js
// Empty

## renderer.js
const base64 = require('js-base64')
async function go() {
  // This URL works fine:
  // const url = "https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer/byteLength"
  // This URL causes seg fault (~2mb)
  const url = "https://media4.giphy.com/media/gd09Y2Ptu7gsiPVUrv/giphy.gif"

  const button = document.getElementById('test')
  const buffer = await (await fetch(url)).arrayBuffer()
  button.textContent += (" Buffer length " + buffer.byteLength)
  const encoded = base64.Base64.fromUint8Array(buffer);
  // Correct: const res = base64.Base64.decode(encoded);
  try {
    const res = btoa(encoded) // crash!
    button.textContent += " Success! " + res.substr(0, 50)
  } catch (e) {
    button.textContent += " Error: " + e
  }
}

document.getElementById('test').addEventListener('click', go);

## styles.css
/* Empty */
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="UTF-8">
	<title>Hello World!</title>
	<link rel="stylesheet" type="text/css" href="./styles.css">
	</head>
	<body>
	<h1>Hello World!</h1>
	<!-- All of the Node.js APIs are available in this renderer process. -->
	We are using Node.js <script>document.write(process.versions.node)</script>,
	Chromium <script>document.write(process.versions.chrome)</script>,
	and Electron <script>document.write(process.versions.electron)</script>.

	<button id="test">Go</button>
	<script>
	// You can also require other files to run in this process
	require('./renderer.js')
	</script>
	</body>
	</html>
	// Modules to control application life and create native browser window
	const {app, BrowserWindow} = require('electron')

	function createWindow () {
	// Create the browser window.
	const mainWindow = new BrowserWindow({
	width: 800,
	height: 600,
	webPreferences: {
	worldSafeExecuteJavaScript: false,
	contextIsolation: false,
	nodeIntegration: true
	}
	})

	// and load the index.html of the app.
	mainWindow.loadFile('index.html')

	// Open the DevTools.
	// mainWindow.webContents.openDevTools()
	}

	// This method will be called when Electron has finished
	// initialization and is ready to create browser windows.
	// Some APIs can only be used after this event occurs.
	app.whenReady().then(createWindow)

	// Quit when all windows are closed, except on macOS. There, it's common
	// for applications and their menu bar to stay active until the user quits
	// explicitly with Cmd + Q.
	app.on('window-all-closed', function () {
	if (process.platform !== 'darwin') {
	app.quit()
	}
	})

	app.on('activate', function () {
	// On OS X it's common to re-create a window in the app when the
	// dock icon is clicked and there are no other windows open.
	if (BrowserWindow.getAllWindows().length === 0) {
	createWindow()
	}
	})

	// In this file you can include the rest of your app's specific main process
	// code. You can also put them in separate files and require them here.
	const base64 = require('js-base64')
	async function go() {
	// This URL works fine:
	// const url = "https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer/byteLength"
	// This URL causes seg fault (~2mb)
	const url = "https://media4.giphy.com/media/gd09Y2Ptu7gsiPVUrv/giphy.gif"

	const button = document.getElementById('test')
	const buffer = await (await fetch(url)).arrayBuffer()
	button.textContent += (" Buffer length " + buffer.byteLength)
	const encoded = base64.Base64.fromUint8Array(buffer);
	// Correct: const res = base64.Base64.decode(encoded);
	try {
	const res = btoa(encoded) // crash!
	button.textContent += " Success! " + res.substr(0, 50)
	} catch (e) {
	button.textContent += " Error: " + e
	}
	}

	document.getElementById('test').addEventListener('click', go);