Install - Problem with Composer

When trying to install ECA Tamper with Composer (composer require 'drupal/eca_tamper:^1.0') I get

Problem 1
- Root composer.json requires drupal/eca_tamper ^1.0 -> satisfiable by drupal/eca_tamper[1.0.0, 1.0.1, 1.0.2, 1.0.3].
- drupal/eca_tamper[1.0.0, ..., 1.0.3] require drupal/tamper ^1.0 -> found drupal/tamper[dev-1.x, 1.0.0-alpha1, 1.0.0-alpha2, 1.0.0-alpha3, 1.x-dev (alias of dev-1.x)] but it does not match your minimum-stability.

- Drupal 9.50
- ECA 1.10
- Tamper is not installed yet

So far - everything got installed cleanly via composer.

Sorry ;-(