Recalling an Email
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There is no "native" ability (as defined by the standard email protocols) that allows you to recall a message once it has been sent.
Some email client/server combinations do allow messages to be recalled, but this is accomplished using proprietary mechanisms. For example, when using Microsoft Outlook with the Microsoft Exchange email server, users can recall a message, which will actually remove it from the recipient's mailbox. This is not a standard feature of email and depends on the mail server being able to control both the sender and recipient accounts. For full details, read the Microsoft Support Article on Recalling an email.
Some email services (such as Google Mail) insert a time delay before messages are sent. You can prevent a message from being sent provided that you act before the time delay expires. This is not "recalling" a message - it is simply cancelling the message before it is sent.
If you want a similar option in Thunderbird, the Send Later add-on delays sending each message and provides the opportunity to change your mind and delete the message from the outbox before it is sent.
The simplest method to delay sending and give yourself time to think is to make Thunderbird work offline (). All messages will be stored locally and will not be sent until you go back online or click the button.