Can't open save files for kdenlive/shotcut with Flatpak 1.2.5 with Devuan 10

I maintain the distribution AVMultimedia which is Devuan 10 based.

I can install flatpak with devuan package (version 1.2.5). I can install apps with 'flatpak install org.kde.kdenlive. What I don’t can is open or save project in kdenlive or shotcut. If I click menu entry, nothing happens. I can’t see anything in the messages when calling kdenlive or shotcut. Any idea?

Do you have xdg-desktop-portal and xdg-desktop-portal-gtk / xdg-desktop-portal-kde installed?

xdg-desktop-portal was installed, xdg-desktop-portal-gtk / xdg-desktop-portal-kde were not installed, but even after installing it, I can’t click to open / save buttons.

Wanted to add here that flatpak install krita, then opening/saving files works in krita, but not in kdenlive. In shotcut I see that changing direktories works and then too saving. So it seems that it is rather only a kdenlive / flatpak file right problem. Opening a already stored project in kdenlive works, but again I can’t click to open / save as buttons.

Maybe you just don’t see the dialog, because it appears behind the main window? (This does happen sometimes with gtk)