What to do when Thunderbird do not show the message in proper format:
Open Thunderbird
Click View -> Messege Body As and make sure Original HTML is selected.
For images attached to messages: click View menu and make sure that Display Attachments Inline is checked.
Open Thunderbird
Click View -> Messege Body As and make sure Original HTML is selected.
For images attached to messages: click View menu and make sure that Display Attachments Inline is checked.