F5 APM V16.x prefill username on logon form

Hi

Any one got this to work on 16.x . I have seen some KB's on previous versions. seems like they have changed it again.

Why oh why do they make it so hard to prefill the username.  You can't prefill unless you make it readonly (WHY). so some JS hack to make it read write. But now it doesn't set all of the right session variables !!!!

I'm using a cookie as a hint to prefill the username. browser is guessing badly - there is only a textbox for the username - click to get to the next box which has the password entry.

I do this as some users are saml connected.

Any one integrated APM with an external login / password forms ?