Focussing on the next field or button.
> And it's a UX problem if a password box is shown by default, because then users who don't have passwords think there's a bug in accessing the resource (because they don't have a password).
Hence why I said it can be hidden.
> If your password manager has a problem with filling in the username, then the problem is with your password manager
For sure not filling username only is a problem/missing feature with Firefox, I didn't claim otherwise. My main use for this feature is not dealing with what I consider to be bad UX, but logging in to sites that for security I don't want FF remembering my password.
> Starting with username-only is an industry standard for any product used in enterprises.
That's the complaint.
There is so much JS, no problem.
Some suggestions: https://www.twilio.com/blog/why-username-and-password-on-two...
But that's the point... how?
It recognizes that when the user confirms they've finished entering their username by clicking some kind of button.
At which point either a password box is shown or the alternative mechanism is shown.
There's no way to know in advance. And it's a UX problem if a password box is shown by default, because then users who don't have passwords think there's a bug in accessing the resource (because they don't have a password).
If your password manager has a problem with filling in the username, then the problem is with your password manager, not with the login flow. Starting with username-only is an industry standard for any product used in enterprises.