test.js

browser window
const { app, net, protocol, BrowserWindow } = require('electron')
const path = require('path')
const { pathToFileURL } = require('url')

protocol.registerSchemesAsPrivileged([
  {
    scheme: 'a',
    privileges: {
      standard: true,
      stream: true,
    }
  }
]);

protocol.registerSchemesAsPrivileged([
  {
    scheme: 'b',
    privileges: {
      standard: false,
      stream: false,
    }
  }
]);

app.whenReady().then(() => {
  protocol.handle('a', (req) => {
    const { host, pathname } = new URL(req.url);
    return new Response('<audio controls src="https://www.learningcontainer.com/wp-content/uploads/2020/02/Kalimba.mp3"></audio>', {
      headers: { 'content-type': 'text/html' }
    })
  })
});

app.whenReady().then(() => {
  protocol.handle('b', (req) => {
    const { host, pathname } = new URL(req.url);
    return new Response('<audio controls src="https://www.learningcontainer.com/wp-content/uploads/2020/02/Kalimba.mp3"></audio>', {
      headers: { 'content-type': 'text/html' }
    })
  })
});


function createWindow() {
  const aWindow = new BrowserWindow()
  aWindow.loadURL('a:')

  const bWindow = new BrowserWindow()
  bWindow.loadURL('b:')

}

app.whenReady().then(() => {
  createWindow()
})