Userscript to show YouTube channel ID next to channel name

sytcid.user.js

// ==UserScript==
// @name        Show YouTube channel ID
// @description Add YouTube channel ID next to channel name for visibility
// @version     4
// @match       https://*.youtube.com/*
// @grant       GM.setClipboard
// ==/UserScript==

(function (window, document, setClipboard) {
  function getChannelId(event) {
    try {
      var detail = event.detail;
      if (!detail.pageType === 'channel') {
        return null;
      }
      return detail.response.response.header.c4TabbedHeaderRenderer.channelId;
    } catch (e) {
      return null;
    }
  }

  function getChannelIdNote() {
    var noteList = document.getElementsByClassName('sytcid-note');
    if (noteList.length > 0) {
      return noteList[0];
    }
  }

  function createChannelIdNote() {
    var note = document.createElement('span');
    note.classList.add('sytcid-note');
    note.style.color = 'red';

    note.appendChild(document.createTextNode('['));

    var idElement = document.createElement('span');
    idElement.classList.add('sytcid-id');
    note.appendChild(idElement);

    note.appendChild(document.createTextNode(']'));

    if (setClipboard) {
      var copyLink = document.createElement('a');
      copyLink.textContent = '(copy ID)';
      copyLink.href = '#';
      copyLink.classList.add('sytcid-copy');
      copyLink.addEventListener('click', function (event) {
        setClipboard(idElement.textContent);
        event.preventDefault();
      });
      note.appendChild(copyLink);
    }

    return note;
  }

  function getChannelNameElement() {
    return document.querySelector('#channel-header #channel-name');
  }

  function updateChannelIdNote(event) {
    var channelIdNote = getChannelIdNote();
    if (!channelIdNote) {
      var channelNameElement = getChannelNameElement();
      if (!channelNameElement) {
        return;
      }

      channelIdNote = createChannelIdNote();
      channelNameElement.appendChild(channelIdNote);
    }

    var channelId = getChannelId(event);
    var channelIdElement = channelIdNote.querySelector('.sytcid-id');
    var copyLink = channelIdNote.querySelector('.sytcid-copy');
    if (channelId) {
      channelIdElement.textContent = channelId;
      if (copyLink) {
        copyLink.style.display = 'inline';
      }
    } else {
      channelIdElement.textContent = 'Could not get channel ID';
      if (copyLink) {
        copyLink.style.display = 'none';
      }
    }
  }

  window.addEventListener('yt-navigate-finish', updateChannelIdNote);
})(window, document, GM.setClipboard);