How do I make apps to use KDE file picker?

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1

On Plasma 6 all apps except KDE native apps use the GTK file picker. I tried adding this to my configuration but nothing seems to work.

{ pkgs, ... }:

{
  xdg.portal = {
    xdgOpenUsePortal = true;
    extraPortals = with pkgs; [
      kdePackages.xdg-desktop-portal-kde
    ];
    config = {
      kde.default = [ "kde" ];
      kde."org.freedesktop.portal.FileChooser" = [ "kde" ];
      kde."org.freedesktop.portal.OpenURI" = [ "kde" ];
    };
  };

  environment.systemPackages = with pkgs; [
    kdePackages.plasma-integration
    xdg-desktop-portal
    xdg-desktop-portal-gtk
    kdePackages.xdg-desktop-portal-kde
    gsettings-qt
    gsettings-desktop-schemas
    gnome-settings-daemon
    kdePackages.plasma-browser-integration
  ];
}

what else do I miss? How do I declaratively set the Dolphin/Qt/KDE file picker globally?