This is an old habit from Microsoft Office Outlook which sets as startup application by default. It is very handy if you don’t have regular time for reading email. However, Mozilla Thunderbird doesn’t come with same solution.
In this tip, I will use Startup Applications Preferences which is GUI for startup programs on Ubuntu. When you download for full version of Ubuntu 18.04, it comes by default. However, I’m not sure about minimal installation.
Add startup program
Click Add, and you will see a window that has Name, Command and Comment inputs. You need to fill name and command, but you don’t need to worry about comment.
|Name||Mozilla Thunderbird - Email client|
When you save, you will see the record which it will be like this
Your Thunderbird is ready to go. All you need to is log out and log in. After that, you will see the email client.