https://duckduckgo.com/?q=utopia+messenger

https://beta.u.is/

Doesn't make it clear if it's OPEN-SOURCE or NOT.

https://beta.u.is/about-utopia

ABOUT UTOPIA
The Utopia ecosystem is the culmination of a multi-year effort by a group of technology enthusiasts dedicated to freedom of self-expression and privacy. We call ourselves the 1984 Group. Among us there are top-notch professionals in almost every IT field, such as cryptography, software, networking engineers and many more. This has been a long and challenging journey. After all this had never been done before! Finally, we present an ecosystem that will change the way the World communicates and handles financial transactions.

WHAT IS UTOPIA?
Utopia is a secure, decentralized ecosystem that utilizes unique peer-to-peer network architecture. There is no central server involved, meaning that there is no single point of failure that, if it failed, would stop the entire system from functioning. Your messages and files will never be stored on third-party servers.

Each user participates in the transmission of network data but only the recipient can decrypt the data. Advanced encryption ensures an interception-proof communication channel to all Utopia users.

WHAT YOU CAN DO USING UTOPIA?
While using Utopia, you can send personal messages or particulate in a group chat (both public and private), send internal uMail (email used only inside the ecosystem), send voice messages, share files with your friends, make financial transactions denominated in our own cryptocurrency called Crypton. All of this in total privacy.

Even better, while using Utopia you will be earning Cryptons through a process called mining which does not slow down your computer. There is nothing more satisfying than using your favorite software and earning simultaneously.

WHY USE UTOPIA OVER OTHER SYSTEMS AND MESSENGERS?
It is important to note that Utopia is not a whitepaper, some abstract idea or statement of intent. This is a fully functional software product ready to be used. This makes Utopia a one-of-a-kind decentralized ecosystem with no true alternative or comparison. Key Privacy features of the Utopia ecosystem:

• A truly decentralized peer-to-peer ecosystem with no point of failure
  
• Interception-proof advanced encryption based on elliptic curves
  
• It cannot be banned by internet censorship
  
• No third-party software is involved, all tools are available within the Utopia ecosystem
  
• No-one collects your data such as Chat messages, Emails, IP address or Geolocation
  
• Local storage is encrypted by 256-bit AES protecting all of your data, history and settings
  

CRYPTON CRYPTOCURRENCY
Crypton is an integral part of the Utopia system. All financial transactions within Utopia are denominated in Crypton.

• Cryptographically secure. Cannot be manipulated by any organization or government
  
• Safe for merchants. Transactions in Crypton are final and cannot be reversed
  
• A merchant interface is readily available
  
• Freedom of payment. Send and get money anywhere in the world at any given time
  
• You are in control of your money. There is no 3rd party with the authority to block your wallet
  
• Confidentiality. Your transactions cannot be viewed by others
  
• Cost-efficient. Transaction fees are at a bare minimum
  
• Mining. You can earn simply by using Utopia with no effect on your computer performance
  

Utopia Press Pack is available.

Demo video:
"Utopia encrypted messenger | Ultra Hacks" ~ Ultra Hacks, 2019-10-07 (12:36) https://www.youtube.com/watch?v=nfBR2QoE2eI