Thank you for your patience. We are thrilled to that replying to a chat message in the desktop client is now available as part of our Public Preview. It is expected to roll out to the public ring over the next several weeks.
For details on switching to the Microsoft Teams Public Preview version, please see : https://aka.ms/TeamsPublicPreview.
We look forward to your preview feedback!
An error occurred while saving the commentBRIAN DAVIDSON commented
Must have feature, I wont be fully moving to Teams until this is added