File picker crashing on arch

am trying to setup Obsidian, but whenever I go to “Open as Vault”, or I try to create a new folder as my vault, the file-picker crashes. I get this error message:

Speicherort“ der Anwendung Portal reagiert nicht. Möchten Sie diese Anwendung beenden? Durch das Beenden werden alle Fenster der Anwendung geschlossen. Ungespeicherte Daten gehen dabei verloren.

Which translates to:

The application Portal is not responding. Do you want to terminate this application? Terminating the application will close all application windows. Any unsaved data will be lost.

I tried it with the Obsidian from pacman, flatpak and AUR. I also tried to remove the Environmentvariables GTK_USE_PORTALandXDG_CURRENT_DESKTOPthen uninstalling thexdg-desktop-portal-gtk`, but that just destroyed everything, so that I only had a Terminal on reboot.

My system:

Archlinux x64
KDE-plasma
wayland