Stylix Icon theme applied to GTK apps but not to QT apps

[ItsLiyua]

I'm trying to set up the stylix iconTheme tool but the icons are only being applied to GTK apps.
I tested it with kdePackages.dolphin and nautilus (both installed via nix-shell -p).
On GTK everything works as expected and on QT as well except for the icons.
The color scheme is being applied as well in QT apps.
The only thing missing are the custom icons.

My stylix configuration looks like this:

{ config, lib, pkgs, stylix, nix-wallpaper, system, ... }: {
  home.packages = [ pkgs.kdePackages.dolphin ];
  gtk.enable = true;
  qt.enable = true;
  stylix = {
    enable = true;
    autoEnable = true;
    base16Scheme = "${pkgs.base16-schemes}/share/themes/catppuccin-mocha.yaml";
    polarity = "dark";
    cursor = {
      package = pkgs.bibata-cursors;
      name = "Bibata-Modern-Ice";
      size = 16;
    };
    iconTheme = {
      enable = true;
      # package = pkgs.catppuccin-papirus-folders;
      package = pkgs.papirus-icon-theme;
      dark = "Papirus-Dark";
      light = "Papirus-Light";
    };
    image = (import ./wallpaper.nix { inherit config; inherit system; inherit nix-wallpaper; }).file;
    fonts = {
      serif = {
        package = pkgs.dejavu_fonts;
        name = "DejaVu Serif";
      };
      sansSerif = {
        package = pkgs.dejavu_fonts;
        name = "DejaVu Sans";
      };
      monospace = {
        package = pkgs.nerd-fonts.jetbrains-mono;
        name = "JetBrains Mono Nerd Font";
      };
      emoji = {
        package = pkgs.noto-fonts-emoji;
        name = "Noto Color Emoji";
      };
    };
    # targets.firefox.colorTheme.enable = true;
    targets = {
      qt.enable = true;
      gtk.enable = true;
    };
  };
}

Not quite sure whether that's a bug or I'm just using it wrong.

Also when opening the qt5ct UI there was a notification about the tool not being configured correctly due to the QT_QPA_PLATFORMTHEME env var not being set. However I opened a terminal and tried to echo it out and the echo command showed it was set to qt5ct. When explicitly setting the env var using the hyprland parameter qt5ct doesn't complain anymore but the icons still don't work.

Thanks for reading.

[danth]

The Stylix icon theme is effectively just passed through to Home Manager's gtk.iconTheme option:

stylix/stylix/hm/icon.nix

Lines 9 to 10 in 5869510

	gtk = {
	iconTheme = {