Hi all, I've been enjoying experimenting with the Office 2016 dark theme, but I've noticed that Outlook is particularly difficult to use, due to the stark dichotomy of dark UI and white message preview. Is there an option (or creative hack) to make the message appear with a dark/black background when there's no defined background color or image? Thanks!
@Greg Edwards interest in this as well, let me know if you find a way. The only thing I've seen is to basically create your own stationary, but that means recipients will see a gray background on their side as well, which is not what we want.
A bit too late, but there are UI XML files in the ProgramData folders for each app that controls some of the base colors. I was looking into to replacing the default Blue highlights that appear when you highlight menu items - the client felt the colors really clashed with branding. The only issue to using this method is if you are using 365 as it updates frequently and replaces the changed file. Not sure about the message background, but it works for Excel sheets and the empty space in Word docs.
If I recall the files are UI.AppName.themexml... so UI.Outlook.themexml