ente/lib/extensions/input_formatter.dart

import "package:flutter/services.dart";

class UpperCaseTextFormatter extends TextInputFormatter {
  @override
  TextEditingValue formatEditUpdate(
    TextEditingValue oldValue,
    TextEditingValue newValue,
  ) {
    return TextEditingValue(
      text: newValue.text.toUpperCase(),
      selection: newValue.selection,
    );
  }
}