Google has given a new experimental feature to Gmail yesterday, allowing users to stop the messages from being sent by mistake.
To turn on this option, you need to go to Settings -> Labs -> Undo Send, and select ‘enable’. Once this feature is activated, you will see a new ‘Undo’ link appear on every sent mail confirmation. Clicked this link will take you back to the composing window allowing you to cancel the delivery or modify the message.
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Unfortunately, ‘Undo Send’ doesn’t really pull back a message that has already sent. This feature only holds your message for 5 seconds so you have a chance for second thoughts.
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