I've no clue what development mode in angular really does... but I'm pretty sure you should turn it off. :P I would bet that prod mode is faster or more stable or whatever... Also there's a console log still in the code. But hey... no project without accidentally commited debug code! :D
One advice in terms of UI: I would add some sort of loading animation to the username input as it takes some time (as you mentioned) for big users.
All in all... Great job!!!
Oh and.... Thanks for being my most loyal follower! ;)
Whoops, I guess I uploaded the wrong version to the production server. Thanks!
And yeah, a spinner on the search bar is a good idea. I think I'll add that tomorrow.