main.js

const electron = require('electron')
const { app, BrowserWindow, Tray } = require('electron')
const shortcut = require('electron-localshortcut');

const fgColor = "#f8f8f8"
const myMsgColor = "#288"
const bgColor = "#284472" // #284472 is also pretty cool, as are #248 and #288

var hideTab = true
let tray = null
var open = false
var win

var launch = () => {
    open = true
    win = new BrowserWindow({
        width: 600, height: 675, icon: __dirname + '/messenger.ico',        
        webPreferences: {
            plugins: true,
            nodeIntegration: false
        },
        frame: false,
    })
    let s = electron.screen.getPrimaryDisplay().workAreaSize
    let _s = win.getSize()
    win.on('closed', () => { win = null; open = false })
    shortcut.register(win, 'Ctrl+Backspace',
     () => { if(win.webContents.canGoBack()) win.webContents.goBack() })
    shortcut.register(win, 'Ctrl+Q', () => { open = false; win.close() })
    shortcut.register(win, 'Ctrl+R', () => { win.reload() })
    shortcut.register(win, 'Ctrl+M', () => { win.minimize() })
    shortcut.register(win, 'Ctrl+Shift+F', 
    () => { win.setFullScreen(!win.isFullScreen()); win.center() })
    shortcut.register(win, 'Ctrl+Y', () => { win.center() })
    shortcut.register(win, 'Ctrl+Shift+I', () => { win.webContents.toggleDevTools() })
    shortcut.register(win, 'Ctrl+Tab', () => {
        if(hideTab) {
            hideTab = false
            win.webContents.insertCSS(`._1enh { display: none; }`)
        }
        else {
            hideTab = true
            win.webContents.insertCSS(`._1enh { display: unset; }`)
        }
    })
    win.loadURL('https://messenger.com/login/')
    win.webContents.on('dom-ready', (e, d) => {
        win.webContents.insertCSS(`
        body { overflow: hidden !important; }
        ._1enh { 
           background-color: ${bgColor} 
        }
        ._1q5- { 
            background-color: ${bgColor} 
        }
        ._nd_ ._hh7 { 
            background-color: ${myMsgColor} !important; 
            color: ${fgColor}; 
        }
        h2, ._2v6o, time, ._ih3, ._1tqi, ._1ht6, ._5rpb, ._1htf, ._1ht7 { 
            color: ${fgColor} !important; 
        }
        ._30yy { 
            border-radius: 100px;
            background-color: ${fgColor} !important;
            opacity: 1 !important; 
        }
        ._39bl {
            background: none !important;
            color: ${fgColor} !important;
        }
        ._4rv9 { background: none !important; }
        ._4ld- { 
            border: solid; 
            border-color: ${fgColor}; 
            border-width: 2px; 
            border-radius: 1000px; 
        }
        ._5742 { -webkit-app-region: drag }
        ._fl2 { -webkit-app-region: no-drag }
        `)
    })
}

app.on('ready', () => {
    tray = new Tray('./messenger.ico')
    tray.on('click', () => {
        if (!open) launch()
        else {
            app.focus()
            win.focus()
        }
    })
    tray.on('right-click', () => {
        app.quit()
        tray.destroy()
    })
    launch()
})