It has various improvements and you can also use your private signal server. I believe it also lets you backup your data! How about that for digital sovereignty.

Are Signal developers trustworthy enough? What about this push for "cloud backups"? There are other flaws in Signal too like being able to monitor people's phone usage and stuff through the notification system. I can't find it now but Signal and WeChat have the same issues, and both received a disclosure. Only WeChat did anything about it. Sad...

Edit: Found it! "Careless Whisper: Exploiting Silent Delivery Receipts to Monitor Users on Mobile Instant Messengers" https://arxiv.org/abs/2411.11194