anchor.diff:        --replace /usr/bin/ $out/bin/ \
         --replace /usr/share/ $out/share/
     '' + stdenv.lib.optionalString (theme != null) ''
  -    cat <<EOF >> $out/lib/slack/resources/app.asar.unpacked/src/static/ssb-interop.js
  +    asar extract $out/lib/slack/resources/app.asar $out/lib/slack/resources/app.asar.unpacked
  +    cat <<EOF >> $out/lib/slack/resources/app.asar.unpacked/dist/ssb-interop.bundle.js
  +
       var fs = require('fs');
       document.addEventListener('DOMContentLoaded', function() {
  -    let tt__customCss = ".menu ul li a:not(.inline_menu_link) {color: #fff !important;}"
         fs.readFile('${theme}/theme.css', 'utf8', function(err, css) {
  -            \$("<style></style>").appendTo('head').html(css + tt__customCss);
  -            \$("<style></style>").appendTo('head').html('#reply_container.upload_in_threads .inline_message_input_container {background: padding-box #545454}');
  -            \$("<style></style>").appendTo('head').html('.p-channel_sidebar {background: #363636 !important}');
  -            \$("<style></style>").appendTo('head').html('#client_body:not(.onboarding):not(.feature_global_nav_layout):before {background: inherit;}');
  +        let s = document.createElement('style');
  +        s.type = 'text/css';
  +        s.innerHTML = css;
  +        document.head.appendChild(s);
         });
       });
       EOF
  +    asar pack $out/lib/slack/resources/app.asar.unpacked $out/lib/slack/resources/app.asar
     '';
   
     meta = with stdenv.lib; {
  
positive.code: { theme ? null, stdenv, fetchurl, dpkg, makeWrapper , alsaLib, atk, cairo,
  cups, curl, dbus, expat, fontconfig, freetype, glib , gnome2, gtk3, gdk_pixbuf,
  libappindicator-gtk3, libnotify, libxcb, nspr, nss, pango , systemd, xorg,
  at-spi2-atk, libuuid
  }:
  
  let
  
negative.code:     gtk3  # needed for GSETTINGS_SCHEMAS_PATH
    ];
  
    nativeBuildInputs = [ makeWrapper nodePackages.asar ];
  
    dontUnpack = true;
    buildCommand = ''
  