I had this problem with the version switch from v1 to v2. At some point the avatars for secret chats appeared again, but only for new chats. I suspect that there was/is a problem with chats initiated in the past and those chats not migrating properly to the new version.
I had this problem with the version switch from v1 to v2. At some point the avatars for secret chats appeared again, but only for new chats. I suspect that there was/is a problem with chats initiated in the past and those chats not migrating properly to the new version.