podman-desktop: derive .desktop entry from upstream .flatpak.desktop

Install the upstream .flatpak.desktop directly instead of hand-maintaining
a makeDesktopItem, rewriting only the launcher command and icon name and
dropping the X-Flatpak key. This keeps Categories and Keywords aligned with
upstream and prevents them from regressing. The --replace-fail patterns
fail the build if upstream renames those lines.

Signed-off-by: kaynetik <aleksandar@nesovic.dev>
(cherry picked from commit 7a77089)

Author: kaynetik

pkgs/by-name/po/podman-desktop/package.nix

@@ -3,13 +3,11 @@
   stdenv,
   fetchFromGitHub,
   makeBinaryWrapper,
-  copyDesktopItems,
   electron_41,
   nodejs-slim_24,
   pnpm_10,
   fetchPnpmDeps,
   pnpmConfigHook,
-  makeDesktopItem,
   darwin,
   nix-update-script,
   _experimental-update-script-combinators,
@@ -96,9 +94,6 @@ stdenv.mkDerivation (finalAttrs: {
     pnpm
     pnpmConfigHook
   ]
-  ++ lib.optionals (!stdenv.hostPlatform.isDarwin) [
-    copyDesktopItems
-  ]
   ++ lib.optionals stdenv.hostPlatform.isDarwin [
     darwin.autoSignDarwinBinariesHook
   ];
@@ -147,6 +142,13 @@ stdenv.mkDerivation (finalAttrs: {
 
         install -Dm644 buildResources/icon.svg "$out/share/icons/hicolor/scalable/apps/podman-desktop.svg"
 
+        # Derive the .desktop entry from upstream to keep it aligned and avoid regressions.
+        install -Dm644 .flatpak.desktop "$out/share/applications/podman-desktop.desktop"
+        substituteInPlace "$out/share/applications/podman-desktop.desktop" \
+          --replace-fail 'Exec=run.sh %U' 'Exec=podman-desktop %U' \
+          --replace-fail 'Icon=io.podman_desktop.PodmanDesktop' 'Icon=podman-desktop'
+        sed -i '/^X-Flatpak=/d' "$out/share/applications/podman-desktop.desktop"
+
         makeWrapper '${electron}/bin/electron' "$out/bin/podman-desktop" \
           --add-flags "$out/share/lib/podman-desktop/resources/app.asar" \
           --set XDG_SESSION_TYPE 'x11' \
@@ -159,20 +161,6 @@ stdenv.mkDerivation (finalAttrs: {
       ''
     );
 
-  # see: https://github.com/podman-desktop/podman-desktop/blob/main/.flatpak.desktop
-  desktopItems = [
-    (makeDesktopItem {
-      name = "podman-desktop";
-      exec = "podman-desktop %U";
-      icon = "podman-desktop";
-      desktopName = appName;
-      genericName = "Desktop client for podman";
-      comment = finalAttrs.meta.description;
-      categories = [ "Utility" ];
-      startupWMClass = appName;
-    })
-  ];
-
   meta = {
     description = "Graphical tool for developing on containers and Kubernetes";
     homepage = "https://podman-desktop.io";