Trigger Home Realm Discovery when setting the email by jQuery instead of typing

I am using Home Realm Discovery on ADFS and Google Apps (on lock.js v9)
That works very well in case the user is typing in her/his email address. Then - as expected - the password input field disappears.

Now I want to preset that field. I am doing this with jQuery:

$('#a0-signin_easy_email').val('manuel.reil@alyne.com');

This works, BUT the HRD (Home Realm Discovery) is not triggered.

Do you know anything that triggers the HRD? Either by jQuery mocking key strokes or with calling something in the lock.js API?

That is not supported in Lock v9, it may be possible to simulate through JS the necessary conditions for Lock to apply the same logic as when the user inputs the email, but I’m not sure what it would take to accomplish that.

Given Lock v9 is no longer fully supported the recommendation would be to use Lock 10 which has built-in support for the feature you mention, more specifically, check the prefill options available in Lock 10.