Vaadin 25: duplicate fields

[javier-godoy]

Describe the bug

In Vaadin 25 the "Username" and "Password" are duplicate. There are also two submit buttons, one for the extended form ("accept") and the other from the framework component ("log in").

Expected behavior

https://addonsv24-staging.flowingcode.com/extended-login

Minimal reproducible example

https://addonsv25-staging.flowingcode.com/extended-login

Add-on Version

1.0.2-SNAPSHOT

Vaadin Version

25.0.3

Additional information

No response