Login works when app run but fails in Selenide test

Question

Been trying to solve this problem for a few days. No joy.

If I run the app locally everything works, can enable and disable users through the admin page even make the test user an admin.

Trying to write Selenide tests, is a learning experience so did not start with the tests because without Selenide experience would have no clue if the failure was because lack of Selenide knowledge or a bug.

The application is Java Springboot with Spring security. Had an earlier problem with CSRF but fix that.

Have run the test in debug mode with a lot of logging.

Example from the log:

[http-nio-auto-1-exec-7] ApplicationData - Application name: Coding Example UNDER_TEST
[http-nio-auto-1-exec-7] DispatcherServlet - Completed 200 OK
[http-nio-auto-1-exec-7] AnonymousAuthenticationFilter - Set SecurityContextHolder to anonymous SecurityContext
[[http-nio-auto-1-exec-8] FilterChainProxy - Securing POST /perform-login
[http-nio-auto-1-exec-8] TokenBasedRememberMeServices - Interactive login attempt was unsuccessful.
[http-nio-auto-1-exec-8] TokenBasedRememberMeServices - Cancelling cookie
[http-nio-auto-1-exec-8] DefaultRedirectStrategy - Redirecting to /login-error

My controller class produces the login and the error page OK, can set breakpoints in these methods and all appears to be fine.

Breakpoints in the user service and the /perform-login method in the controller are never called.

All this code works fine when run from IntelliJ or from the command line just when run by Selenide test it fails!

The simple test:

@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
public class LoginTest {

    @LocalServerPort
    private int port = 0;

    @Test
    public void adminCanLoginByUsername() {
        open("http://localhost:" + port + "/login");
        $(By.name("username")).setValue("Admin");
        $(By.name("password")).setValue("p455word");
        $("#submit").click();
        assertEquals("http://localhost:"+port+"/index", webdriver().object().getCurrentUrl());
        assertTrue($("#admin-menu-item").isEnabled());
    }
}

Using JDK 21, Springboot 3.2.3, selenide 7.2.1, Chrome with appropriate diver.

Any ideas, what have I missed?