There are several possible reasons why the “Trash” in Thunderbird disappears.

Solution (Subscription)
Right-click on the email address in the left pane of Thunderbird and click “Subscription”.

In the window that appears, check the check box to the right of the “Trash” folder.


Click “OK” to confirm.
Why does the “Trash” in Thunderbird disappear?
There are several possible reasons why the “Trash” in Thunderbird disappears.
- Damaged database file:
- Thunderbird manages each folder, including the “Trash”, in a database file. If this file becomes damaged, the “Trash” may not be displayed.
- Impact of antivirus software:
- Antivirus software may mistakenly identify the “Trash” file as a threat and delete it when you close Thunderbird.
- IMAP synchronization issue:
- If you use an IMAP account, your actions on other devices or in the web interface may be synchronized, making it appear as if the “Trash” has disappeared.
- Unsubscribing from a folder:
- When you unsubscribe from the Trash folder in your IMAP account, it may disappear.
- Profile issues:
- If the Trash file in your Thunderbird profile folder is deleted for any reason, the Trash will disappear.
These issues may cause your Thunderbird Trash to suddenly disappear.
Results
This should bring back your Trash folder. If your Trash folder has disappeared, we recommend trying the steps above.