FadeInOutElectronWindow.ts

import { remote, BrowserWindow } from 'electron';

const fadeWindowOut =  (
    _window: BrowserWindow,
    step: number = 0.1,
    fadeEveryXSeconds: number = 10
  ) =>  {
    let opacity = _window.getOpacity();
    const interval = setInterval(() => {
      if (opacity <= 0) window.clearInterval(interval);
      _window.setOpacity(opacity);
      opacity -= step;
    }, fadeEveryXSeconds);
    return interval;
  }

const fadeWindowIn = (
    _window: BrowserWindow,
    step: number = 0.1,
    fadeEveryXSeconds: number = 10
  )  => {
    let opacity = _window.getOpacity();
    const interval = setInterval(() => {
      if (opacity >= 1) window.clearInterval(interval);
      _window.setOpacity(opacity);
      opacity += step;
    }, fadeEveryXSeconds);
    return interval;
  }


// fade-out window...
let fadeOutWindowTimeIntervalRef = fadeWindowOut(remote.getCurrentWindow(), 0.1, 2)

// if you want to stop fade-out at will...
window.clearInterval(fadeOutWindowTimeIntervalRef);

// fade-in window...
let fadeInWindowTimeIntervalRef = fadeWindowIn(remote.getCurrentWindow(), 0.1, 2)

// if you want to stop fade-in at will...
window.clearInterval(fadeInWindowTimeIntervalRef);