16.99.1 - Bug with Draft emails

We have noticed that if you type a new email in version 16.99.1 and you draft the email in a non-popped window, if you go back to that draft email in your draft folder, the information you have type is missing. 

However, if you type in a popped window, the draft saves.

This is the setting you need to set so all new emails and replies are in a popped window interface.

It would be great if we could get a bug free release soon team. This one is a massive issue with staff members working on emails, only to find the information is lost if they aren't typing or replying in a new window.