fluffychat/lib/utils/string_extension.dart

extension StringCasingExtension on String {
  String removeDiacritics() {
    const withDia =
        'ÀÁÂÃÄÅàáâãäåÒÓÔÕÕÖØòóôõöøÈÉÊËèéêëðÇçÐÌÍÎÏìíîïÙÚÛÜùúûüÑñŠšŸÿýŽž';
    const withoutDia =
        'AAAAAAaaaaaaOOOOOOOooooooEEEEeeeeeCcDIIIIiiiiUUUUuuuuNnSsYyyZz';

    String str = this;
    for (int i = 0; i < withDia.length; i++) {
      str = str.replaceAll(withDia[i], withoutDia[i]);
    }

    return str;
  }
}