This is DeltaChat desktop client but not with the default Electron. Compile instructions for Debian, Arch Linux and openSUSE. One Linux distribution has this packaged : NixOS, package name kdeltachat-unstable. The software developer is also active in the DeltaChat forum. Posting this here to give this project some more attention cause it would be nice to see less Electron and more Kirigami (or Tauri ?).
I am not alone wanting to see screenshots of softwares before even installing them. If you refuse to provide screenshots because someone is not saying please, expect many will not try your DeltaChat client. Over and out.
Compile it yourself! File a bug report with the software developer! (I’m just the messenger of this post) I’ve shared the web link of the project for people who dislike having too many Electron based applications on their computer, like people using older hardware. You may be fine with the Electron based one, screen shots of that here : https://delta.chat/en/