Display Only Unread Messages in Thunderbird
Follow these steps to see only unread mail in Mozilla Thunderbird:
Select the Quick Filter toggle button in the toolbar just above your messages. The Quick Filter Toolbar will appear just below the button. Select the Unread button. This causes all your read messages to disappear and only your unread messages are visible. When you are ready to see all your emails again, click the same Unread button to show your read messages again.
Alternate Method to Show Only Unread Messages
You can also show unread messages via the following method.
Select View > Toolbars > Customize from the Thunderbird menu bar. Scroll to the bottom of the list of icons in the window that opens and find the Mail Views icon. Drag and drop the Mail Views icon on the toolbar to add View followed by a drop-down menu to the toolbar. Click Done to close the Customize window. Using the View drop-down menu, select Unread to display only unread messages. To see all your emails again, select All in the View drop-down menu.
Other Available Options in the View Drop-Down Menu
Using the View drop-down menu, you can also select Not Deleted mail and filter for mail that you have tagged Important, Work, Personal, To Do, or Later. The custom views you can select are:
People I Know Recent Mail Last 5 Days Not Junk Has Attachments
Select Unread Folders
You can also read unread messages in Thunderbird by clicking View in the menu bar and selecting Folders > Unread. This setting shows the folders that contain unread messages, but it shows the entire content of those folders, not only the unread messages.
