For reference:
https://github.com/mozilla/pdf.js/issues/15571#issuecomment-1278141781
const rgb = this._colors.get(name);
    if (!rgb) {
      return name;
    }
    return Util.makeHexColor(...rgb);
  }
}
/**
 * A pdf has several pages and each of them when it will rendered
 * will have an AnnotationEditorLayer which will contain the some
 * new Annotations associated to an editor in order to modify them.
 *
 * This class is used to manage all the different layers, editors and
 * some action like copy/paste, undo/redo, ...
 */
class AnnotationEditorUIManager {