Yes, after the latest update MS Office is now also capable of supporting the OSX Dark Mode. Nice, but rather annoying for MS Outlook I must say, the dark mode just makes reading the different panes very challenging. I went looking for an option in the UI that allowed me to change the default, I couldn’t find it, unfortunately, but I did find a way to disable it through the command line. For MS Outlook, in particular, this is how you do it:
defaults write com.microsoft.Outlook NSRequiresAquaSystemAppearance -bool yes
You can do this for other apps as well if you want, simply change the identifier string of Outlook (com.microsoft.Outlook) with the string of the app you want to disable it for. If you don’t know the string you can do the following to find it:
osascript -e 'id of app "Outlook"'
In the above example, I am looking for the identifier of Outlook, but this could be “Spotify” or anything else as well of course. Figured I would share this, as I found myself searching for half an hour. Note that you need to close/open the app after making the change!