My Flashplayer npapi plugin package no longer works

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1

Until recently, i got away modifying the old Nixpkgs expression to be able to use libflashplayer on Palemoon (a browser that still supports the plugin) and it worked really well, but after a flake update some monthes ago, the browser can’t find the plugin anymore. Installing the plugin in the traditional way by putting the npapi inside ~/.mozilla/plugins and running Palemoon through steam-run still works.

My nix expression:

{ stdenv
, lib
, fetchurl
, alsaLib
, atk
, bzip2
, cairo
, curl
, expat
, fontconfig
, freetype
, gdk-pixbuf
, glib
, glibc
, graphite2
, gtk2
, harfbuzz
, libICE
, libSM
, libX11
, libXau
, libXcomposite
, libXcursor
, libXdamage
, libXdmcp
, libXext
, libXfixes
, libXi
, libXinerama
, libXrandr
, libXrender
, libXt
, libXxf86vm
, libdrm
, libffi
, libglvnd
, libpng
, libvdpau
, libxcb
, libxshmfence
, nspr
, nss
, pango
, pcre
, pixman
, zlib
, p7zip
}:

let
  arch =
    if stdenv.hostPlatform.system == "x86_64-linux" then
      "x86_64"
    else if stdenv.hostPlatform.system == "i686-linux"   then
      "i386"
    else throw "Flash Player is not supported on this platform";
  flash_suffix =
    if stdenv.hostPlatform.system == "x86_64-linux" then
      "64"
    else
      "32";
  lib_suffix =
    if stdenv.hostPlatform.system == "x86_64-linux" then
      "64"
    else
      "";
in
stdenv.mkDerivation rec {
  pname = "flashplayer";
  version = "32.0.0.465";

  src = fetchurl {
    url =
      "http://files3.swfchan.com/end/FlashPluginsFixed_32.0.0.465_WindowsLinux.7z";
    hash =
      "sha256-rcBEyisUhx3i5SgXzZRqV/I/JhEMkMo+MgPSOHy66/8=";
  };

  nativeBuildInputs = [ p7zip ];

  sourceRoot = ".";

  dontStrip = true;
  dontPatchELF = true;

  preferLocalBuild = true;

  installPhase = ''
    mkdir -p $out/lib/mozilla/plugins
    cp -pv FlashPluginsFixed_32.0.0.465_WindowsLinux/linux/linux_${flash_suffix}-bit_NPAPI_libflashplayer--fixed.so $out/lib/mozilla/plugins/libflashplayer.so
    chmod +x $out/lib/mozilla/plugins/libflashplayer.so
    patchelf --set-rpath "$rpath" \
      $out/lib/mozilla/plugins/libflashplayer.so
  '';

  passthru = {
    mozillaPlugin = "/lib/mozilla/plugins";
  };

  rpath = lib.makeLibraryPath
    [ stdenv.cc.cc
      alsaLib atk bzip2 cairo curl expat fontconfig freetype gdk-pixbuf glib
      glibc graphite2 gtk2 harfbuzz libICE libSM libX11 libXau libXcomposite
      libXcursor libXdamage libXdmcp libXext libXfixes libXi libXinerama
      libXrandr libXrender libXt libXxf86vm libdrm libffi libglvnd libpng
      libvdpau libxcb libxshmfence nspr nss pango pcre pixman zlib
    ];

  meta = {
    description = "Adobe Flash Player browser plugin";
    homepage = "http://swfchan.com/end/";
    license = lib.licenses.unfree;
    platforms = [ "x86_64-linux" "i686-linux" ];
  };
}

Running nixos unstable