It was last Sept. that YouTube had started experimenting with “Profile Cards”, which allows you to see a user’s history & previous comments. This feature has been rolled out now to all on Android.
YouTube launches Profile cards that show a user’s comment history – TechCrunch
Last September, YouTube began testing a new feature called profile cards, which showed a user’s public information and comment history on the current channel. The feature was touted as a way for creators to more easily identify their biggest fans by offering easy access to their past comments. Now, YouTube is launching the product to the general public, initially on Android.
Link: https://techcrunch.com/2020/01/15/youtube-launches-profile-cards-that-show-a-users-comment-history/
via: TechCrunch