anchor.diff:      src = fetchurl {
         urls = [
           "https://download.geogebra.org/installers/6.0/GeoGebra-Classic-6-MacOS-Portable-${version}.zip"
  -        "https://web.archive.org/web/20210101214236/https://download.geogebra.org/installers/6.0/GeoGebra-Classic-6-MacOS-Portable-${version}.zip"
  +        "https://web.archive.org/web/20210406084052/https://download.geogebra.org/installers/6.0/GeoGebra-Classic-6-MacOS-Portable-${version}.zip"
         ];
  -      sha256 = "13g05d45j6dn9zwxpxnln83j7w1cvcd7l8jnir30pxlmdi7h8r78";
  +      sha256 = "0fa680yyz4nry1xvb9v6qqh1mib6grff5d3p7d90nyjlv101p262";
       };
   
       dontUnpack = true;
  
positive.code:     src = fetchurl {
        urls = [
          "https://download.geogebra.org/installers/6.0/GeoGebra-Linux64-Portable-${version}.zip"
          "https://web.archive.org/web/20210101214511/https://download.geogebra.org/installers/6.0/GeoGebra-Linux64-Portable-${version}.zip"
        ];
        sha256 = "0xxzmphbfvmhnxnc1pkjgdhccjndyzmlvvaa8xfdrvswwwk7zh43";
      };
  
      dontConfigure = true;
  
negative.code: { lib, stdenv, unzip, fetchurl, electron_6, makeWrapper, geogebra }:
  let
    pname = "geogebra";
    version = "6-0-631-0";
  
    srcIcon = geogebra.srcIcon;
    desktopItem = geogebra.desktopItem;
  