Change:
<ins> { lib , stdenv , buildNpmPackage , fetchFromGitHub , imagemagick , makeWrapper , makeDesktopItem , copyDesktopItems , electron_28 }: let electron = electron_28; in buildNpmPackage rec { pname = "blockbench"; version = "4.9.4"; src = fetchFromGitHub { owner = "JannisX11"; repo = "blockbench"; rev = "v${version}"; hash = "sha256-z4hr1pQh7Jp/DB8+pxwuHvi4gvTHHVn0yrruwnXm2iM="; }; nativeBuildInputs = [ imagemagick # for icon resizing makeWrapper copyDesktopItems ]; npmDepsHash = "sha256-onfz+J77jNIgdc7ALiyoXt1CdTyX/C7+bKwtpJm+H+I="; env.ELECTRON_SKIP_BINARY_DOWNLOAD = 1; npmBuildScript = "bundle"; postBuild = '' npm exec electron-builder --  --dir  -c.electronDist=${electron}/libexec/electron  -c.electronVersion=${electron.version} ''; installPhase = '' runHook preInstall mkdir -p $out/share/blockbench cp -r dist/*-unpacked/{locales,resources{,.pak}} $out/share/blockbench for size in 16 32 48 64 128 256 512; do mkdir -p $out/share/icons/hicolor/"$size"x"$size"/apps convert -resize "$size"x"$size" icon.png $out/share/icons/hicolor/"$size"x"$size"/apps/blockbench.png done makeWrapper ${lib.getExe electron} $out/bin/blockbench  --add-flags $out/share/blockbench/resources/app.asar  --add-flags "''${NIXOS_OZONE_WL:+''${WAYLAND_DISPLAY:+--ozone-platform-hint=auto --enable-features=WaylandWindowDecorations}}"  --inherit-argv0 runHook postInstall ''; # based on desktop file found in the published AppImage archive desktopItems = [ (makeDesktopItem { name = "blockbench"; exec = "blockbench %U"; icon = "blockbench"; desktopName = "Blockbench"; comment = meta.description; categories = [ "3DGraphics" ]; startupWMClass = "Blockbench"; terminal = false; }) ]; meta = { changelog = "https://github.com/JannisX11/blockbench/releases/tag/${src.rev}"; description = "Low-poly 3D modeling and animation software"; homepage = "https://blockbench.net/"; license = lib.licenses.gpl3Only; mainProgram = "blockbench"; maintainers = with lib.maintainers; [ ckie tomasajt ]; broken = stdenv.isDarwin; }; } </ins>

Discussion:
Package name: blockbench-electron Latest released version: 4.9.3 <!-- Search your package here: --- Current version on the unstable channel: 4.8.1 Current version on the stable/release channel: 4.8.1 <!-- Type the name of your package and try to find an open pull request for the package If you find an open pull request, you can review it! There's a high chance that you'll have the new version right away while helping the community! --- Notify maintainers <!-- If the result shows no maintainers, tag the person that last updated the package. --Misc: Noticed this when trying to enter a nix shell with this package, resulting in an electron-25.9.0 EOL error. Note for maintainers: Please tag this issue in your PR. Add a :+1: [reaction] to [issues you find important]. [reaction]: [issues you find important]:
Okay, so I took a look at updating blockbench to a version with uses and but it looks like after 2 seconds, electron crashes. It's probably got to do something with , but I don't have much experience with it. Tried to debug it with , but it didn't really show me anything helpful. I even tried packaging from source, but it has the same issue.
Okay, so I did some more testing, and it looks like itself is the issue, and above work fine. I'll make a PR with the update.