Well, I'm not really sure if Gmail's alert feature is something new or has been around quite a long time.
Earlier, I was replying an email to a friend and I mentioned that I have "attached file" which I sent before the email I am about to reply. After clicking Send, I was prompted with "Did you mean to attach files?", "You wrote "attached files" in your message, but there are no files attached. Send anyway?
At first I thought I've attached a new file and failed but I realized I'm not attaching a file again and so I clicked the Send button again. Then, I was prompted with the message I mentioned above and at that moment I read everything the message said. After reading it I was amazed again with Gmail's features. It's really that simple feature but something that is very functional for regular email users who always mentioned "attached file/s".
So, next time you use your Gmail be sure to try this feature.
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