Would be good to:
1. Show progress animation;
2. Lock [Log In] button;
3. Have a timeout for login operation with error show in the end and button unlocked for another attempt.

Currently auth fails in browser with error below

Gateway Timeout

The proxy server did not receive a timely response from the upstream server.
Reference #1.5434d417.1452674127.644f0c55

which makes installer to look like being in broken state:

• no errors;
• [Log In] can be pressed many times without any reaction