[Bug]: Kernel Logos don't seem to show up and Haskell syntax highlighting doesn't work

[MMesch]

Current Behavior

I have a working config of jupyenv with a Python and a Haskell kernel. They both work fine but they don't have logos and the Haskell kernel has no syntax highlighting. I am unsure whether it's my configuration or something in the kernel config that doesn't pass these arguments correctly. The iHaskell kernel explicitly has a --codemirror flag that is used here: https://github.com/tweag/jupyenv/blob/main/modules/kernels/haskell/default.nix#L44 but it doesn't seem to work.

Expected Behavior

I'd expect to see Python and Haskell logos on the main jupyterlab entry page.
I'd expect to have syntax highlighting for iHaskell

Steps To Reproduce

run this gist with nix run: https://gist.github.com/MMesch/16fb1c2f80c775fb75af5618f945c1d4

OS

- system: `"x86_64-linux"`
 - host os: `Linux 5.15.90, NixOS, 23.05 (Stoat), 23.05.20230131.e1e1b19`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.13.2`
 - channels(matto): `"home-manager-22.05.tar.gz, nixos-22.05, unstable"`
 - channels(root): `"home-manager-22.05.tar.gz, nixos-22.05, nixos-unstable"`
 - nixpkgs: `/etc/channels/nixpkgs`

Version

see gist

Additional Context

No response

Relevant log output

No response