NVDA remains silent and does not give any info bout the automatic suggestions in the address fields in the compose message of www.gmail.com.
Steps to reproduce:

1. Open www.gmail.com.
2. Login to your account.
3. Press ALT+C to open compose message window.
4. Go to the address edit field, To, Cc.
5. Type in a few characters for the address already resent in the contacts list.
6. No automatic suggestions are read.
7. TAB to input and address. No information is read by NVDA