init

modules/nixos/fonts/fhs-fonts.nix

@@ -0,0 +1,33 @@
+{
+  config,
+  pkgs,
+  ...
+}: {
+  ###################################################################################
+  #
+  #  Copy from https://github.com/NixOS/nixpkgs/issues/119433#issuecomment-1326957279
+  #  Mainly for flatpak
+  #    1. bindfs resolves all symlink,
+  #    2. allowing all fonts to be accessed at `/usr/share/fonts`
+  #    3. without letting /nix into the sandbox.
+  #
+  ###################################################################################
+
+  system.fsPackages = [pkgs.bindfs];
+  fileSystems = let
+    mkRoSymBind = path: {
+      device = path;
+      fsType = "fuse.bindfs";
+      options = ["ro" "resolve-symlinks" "x-gvfs-hide"];
+    };
+    aggregatedFonts = pkgs.buildEnv {
+      name = "system-fonts";
+      paths = config.fonts.fonts;
+      pathsToLink = ["/share/fonts"];
+    };
+  in {
+    # Create an FHS mount to support flatpak host icons/fonts
+    "/usr/share/icons" = mkRoSymBind (config.system.path + "/share/icons");
+    "/usr/share/fonts" = mkRoSymBind (aggregatedFonts + "/share/fonts");
+  };
+}