For reference:
https://github.com/mozilla/pdf.js/issues/15571#issuecomment-1278141781
#activeEditor = null;
  #allEditors = new Map();
  #allLayers = new Map();
  #commandManager = new CommandManager();
  #currentPageIndex = 0;
  #editorTypes = null;
  #eventBus = null;
  #idManager = new IdManager();
  #isEnabled = false;
  #mode = AnnotationEditorType.NONE;
  #selectedEditors = new Set();
  #boundCopy = this.copy.bind(this);
  #boundCut = this.cut.bind(this);
  #boundPaste = this.paste.bind(this);
  #boundKeydown = this.keydown.bind(this);
  #boundOnEditingAction = this.onEditingAction.bind(this);
  #boundOnPageChanging = this.onPageChanging.bind(this);
  #previousStates = {
    isEditing: false,
    isEmpty: true,