Open Emails in Outbox still sent

I always have “Send Messages Immediately” disabled because it never fails, after I click Send, I will remember I forgot something.

In Outlook, if I went back and reopened a message in my Outbox, I could leave it open and it would not be sent out.  This was handy if I needed to research something before sending the message.

I did this the other day with EM Client.  While I had the message open and was adding another paragraph, I realized that my original message went out.  If I made the changes and clicked send, and new message appeared in my Outbox.

Is this the proper behavior?  Is there anyway to pause a message from going out without deleting it?

Hello, messages in the Outbox are considered prepared for sending, once the send action is performed either by using the “Send and Receive” button or when automatic sync process is due, the message will be uploaded to the server and later moved into your Sent folder if you’re using IMAP with your account. Unfortunately there’s no option that would allow you to keep the message in Outbox after sending.