Image.nvim backend: regarding #3685

[Mcrtin]

[I'm on unstable nixos + home-manager + https://github.com/Mcrtin/nvim ]
I can't seem to get the MRE from #3685 to run.
I believe it's because the default package for image is vimPlugins.image-nvim, which is Version: 1.3.0-1-unstable-1.3.0-1 in nixpkgs and the sixel backend is only introduced in 1.4
So now I'm wondering how OP in #3685 got that snippet to run without changing the package cuz I'm getting

Error detected while processing /nix/store/nbmmbz792jibp78rk979w3pl4g3
qlzpw-init.lua:
E5113: Error while calling lua chunk: ...mPackages/start/vimplugin-plu
gin-pack/lua/image/init.lua:0: module 'image/backends/sixel' not found
:
        no field package.preload['image/backends/sixel']
        cache_loader: module 'image/backends/sixel' not found
        cache_loader_lib: module 'image/backends/sixel' not found
        no file '/nix/store/16z3mn55dl2y3n1vnqriha9wbdqv7xgb-luajit