How can I enable Collapsed Reply Threads (Beta) for my account?
Threads organize conversations within channels, and threads enable users to discuss topics without adding noise to channels or Direct Messages.
Collapsed Reply Threads (Beta) offers an enhanced experience for users communicating in threads and replying to messages. You can enable this feature for your account by going to Account Settings > Display > Collapsed Reply Threads (Beta).
Learn more about the features and known issues in the Mattermost documentation.
References
Mattermost Documentation