A Greasemonkey script to block certain links on all websites

blacklistlinks.js

'use strict'

const blacklist = [
  'codegolf.stackexchange.com',
  'puzzling.stackexchange.com',
]

/*
Move all children of node to right before node.
*/
function unpackTag(parent, node) {
  while (node.hasChildNodes()) {
    parent.insertBefore(node.firstChild, node)
  }
}

{
  const links = document.body.getElementsByTagName('a')
  let i = 0
  while (i < links.length) {
    const link = links[i]
    const href = link.getAttribute('href')
    if (href && blacklist.some(url => href.includes(url))) {
      const parent = link.parentNode
      unpackTag(parent, link)
      parent.removeChild(link)
    } else {
      ++i
    }
  }
}