@Nullable
  public String getUserNameForUrl(@NotNull String url) {
    for (UrlAndUserName urlAndUserName : myState.visitedUrls) {
      if (urlAndUserName.url.equalsIgnoreCase(url)) {
        return urlAndUserName.userName;
      }
    }
    return null;
  }
@Nullable
  public String getUserNameForUrl(@NotNull String url)