How To Enable Offline Mode In Thunderbird
The Offline mode in Thunderbird is useful lets you compose emails and also download and read previous messages.
Here is how to use it:
To go offline, click on File >Offline.
Then select Work Offline.
So, the icon at the bottom of the Thunderbird window will change indicating that offline mode is now enabled.
During this mode, you can still draft email messages. Click on the Write button as before....