Refined GitHub Copilot UI.user.js

// ==UserScript==
// @name         Refined GitHub Copilot UI
// @license      MIT
// @version      0.0.1
// @description  Remove clutter in the GitHub Copilot UI
// @author       Bjorn Lu
// @match        https://github.com/**
// @icon         https://www.google.com/s2/favicons?sz=64&domain=github.com
// @grant        none
// ==/UserScript==

;(function () {
  'use strict'

  run()

  // listen to github page loaded event
  document.addEventListener('pjax:end', () => run())
  document.addEventListener('turbo:render', () => run())

  // Also check for changes for the first 3 seconds with React-based UI
  const debouncedRun = debounce(run, 200)
  const observer = new MutationObserver(() => debouncedRun())
  observer.observe(document.body, { childList: true, subtree: true })
  setTimeout(() => observer.disconnect(), 3000)
})()

function run() {
  if (location.pathname.startsWith('/copilot')) {
    // Remove useless sidebar links
    removeElement('li', 'a[href="/copilot/agents"]')
    removeElement('li', 'a[href="/copilot/spaces"]')
    removeElement('li', 'a[href="/spark"]')

    // Remove useless "Agent sessions" sidebar section
    removeElement(
      'div[class^="SidebarNavigation-module__sectionContainer"]',
      'a[href^="/copilot/tasks"]'
    )

    // Remove useless command starters
    removeElement('div[class^="NewConversation-module__commandStarters"]')

    // Remove useless "Recent agent sessions" section AGAIN
    removeElement('div[class^="NewConversation-module__agentListContainer"]')
  }
}

/**
 * @param {string} selector
 * @param {string} [containsSelector]
 */
function removeElement(selector, containsSelector) {
  const query = containsSelector
    ? `${selector}:has(${containsSelector})`
    : selector
  const el = document.querySelector(query)
  if (el) {
    el.remove()
  } else {
    console.warn(`Element not found: ${query}`)
  }
}

function debounce(fn, wait) {
  let timeout
  return function (...args) {
    clearTimeout(timeout)
    timeout = setTimeout(() => fn.apply(this, args), wait)
  }
}