The DomCrawler component docs [state](https://symfony.com/doc/current/components/dom_crawler.html#forms) that the `selectButton()` method finds a button by its `label` or `id`. The Symfony Testing docs [state](https://symfony.com/doc/current/testing.html#forms) that the `selectButton()` methods finds a button by its `value`, `id`, `alt` or `name` attributes. One or both of these must be incomplete or incorrect, though I'm not sure which.