The option of encrypted conversations was added to Messenger, which is being developed as part of Facebook, some time ago. They are end-to-end encrypted, so messages sent in such conversations are not saved on Meta's servers. From now on, these conversations will be more colorful and users will be able to customize the appearance of the window in such conversations.
Modifications to the window in secret conversations will include the addition of standard functions available in Messenger, i.e. setting nicknames, chat themes, the use of emoticons, but it will also be possible to react to sent messages. Moreover, on Android it will even be possible to add a secret conversation to the familiar "bubble" form. Meta announces that this is not the end of the news regarding this Messenger function.