Steps to Reproduce:
1. Open any existing Transaction (ex. Sales Order) in View Mode .
2. Hover the mouse pointer in the More Actions Menu, then click Email.
Redirects user to the Transactions tab dashboard in the current window.
This action automatically sends out the Transaction to the Customer. If users wants to edit the Email before it goes out to the customer navigate to Setup > Company > Email Preferences > Email and then set Use Popup For Main Transaction Email Button = True. When users perform the same action again after doing this, users now have a New Email Message pop up page instead of being directed to the Transactions tab dashboard.