How do I send an email using the old Gmail compose window?
Here's how to send a message using the old Gmail compose window.
1. For a new message, click Old Compose at the top of the compose window. (Note: this will only appear on new messages that have not been edited.) This also applies to new Gmail.
2. If you are replying to an existing message, click More at the top of the inline reply window, and select Reply from the drop-down:
Currently, this is only available for Gmail and not Inbox. Replies in new Gmail do not yet have a way to send from Old Compose.