pair device did not work - flare window empty no chats there

Did a build a Linux Mint 22.2 amd64

git clone https://gitlab.com/schmiddi-on-mobile/flare cd flare sudo apt-get install librust-gsk4-sys-dev sudo apt-get install protobuf-compiler sudo apt-get install librust-libadwaita-sys-dev sudo apt-get install librust-libadwaita-sys-de sudo apt-get install librust-libadwaita-sys-dev sudo apt install pkg-config libgtksourceview-5-dev sudo apt install pkg-config libadwaita-1-dev cargo check cargo build --release

sudo mkdir -p /usr/local/share/glib-2.0/schemas/
sudo cp data/de.schmidhuberj.Flare.gschema.xml /usr/local/share/glib-2.0/schemas/
sudo /usr/bin/glib-compile-schemas /usr/local/share/glib-2.0/schemas

$ ./flare

did then paring the device by scanning QR-Code

but the window keeps empty

What did I wrong ?

But some phonenumbers are there so I can select an start a new chat but a lot of unknown contacts

run "sync contacts" did nothing change