Chrome: 65.0.3325.0
Firefox: ESR 52
NVDA: 2017.4

Steps to repro:
# In Chrome, Sign into hangouts.google.com
# With NVDA running, press the 'New Conversation' button
# Focus the edit box
# Begin typing the name of a contact
# Notice NVDA does not read autocompletion
# Press down arrow a few times to change the selected contact
# Notice NVDA does not announce any of these options nor does the edit box get updated with the new contact

Expected: NVDA should read autocomplete suggestions and contact list with arrows while edit box has focus. It should also read the message "Press tab to add to hangout, press enter to start a private conversation'

Actual: It is very difficult for a user to create a hhangout with multiple users. NVDA user must exit forms mode to access search results and can only press enter to open a private conversation

# In Firefox, Sign into hangouts.google.com
# With NVDA running, press the 'New Conversation' button
# Focus the edit box
# Begin typing the name of a contact
# Notice NVDA immediately starts reading suggestions
# Press down arrow a few times to change the selected contact
# Notice NVDA announces contacts and the edit box is updated with the new contact

Expected: Works as expected. Users are able to create hangouts with any number of contacts