electron/docs/fiddles/native-ui/external-links-file-manager/renderer.js

const { shell } = require('electron')
const os = require('node:os')

const exLinksBtn = document.getElementById('open-ex-links')
const fileManagerBtn = document.getElementById('open-file-manager')

fileManagerBtn.addEventListener('click', (event) => {
  shell.showItemInFolder(os.homedir())
})

exLinksBtn.addEventListener('click', (event) => {
  shell.openExternal('https://electronjs.org')
})

const links = document.querySelectorAll('a[href]')

for (const link of links) {
  const url = link.getAttribute('href')
  if (url.indexOf('http') === 0) {
    link.addEventListener('click', (e) => {
      e.preventDefault()
      shell.openExternal(url)
    })
  }
}