The first problem I am running into is how to group AuthRequest objects / form fields. For example, if we have three account creation providers: local password, captcha and facebook, then we probably want to check the captcha on passwords but not on a Facebook login. It is not clear how to do that. Should it be hardcoded into the captcha provider?

On the other side, it will probably make the life of the sitebuilder easier if the Facebook button and the username/password fields do not have to be in the same form element; but that means they are not submitted together and that's not something frontend code can safely decide.

I'm not sure, what extensions we have and how complex modifications they made to the login form, but what about a separation of authproviders. Providers that link to another auth service (e.g. Facebook, Google, Twitter or something else) normally need a button only, are Spam bot protected by the auth service and therefore shouldn't require any additional input (except the keep login checkbox, e.g.). These providers could set a specific class member and should ignore any other form input.

Any other auth provider (CAPTCHA, Token, domain (for LdapAuthentication, e.g.) normaly require any kind of data and checks?

I've adjusted the title and the blocked tasks to match the new use for this task.