Thunderbird is open but the main icon in unity-panel doesn't show that I received an email. I would like that icon change when I receive an email. Take a look at screenshot.
When I receive an email, there is a notification sound but no pop up. I am using Thunderbird 38.5.1 on Ubuntu 14.04 and my account is on Gmail.
Also there is another problem that I like to fix: desktop notification doesn't work.