Problem

Running nvim 0.11.1 on nixos with nvim --clean test.txt writes a few numbers delimited by semicolons and exits. The output is not deterministic. One example output is ;80;159;2080;1908.

Running nvim -V1 -v gives

NVIM v0.11.1
Build type: Release
LuaJIT 2.1.1741730670

   system vimrc file: "$VIM/sysinit.vim"
  fall-back for $VIM: "
/nix/store/j1pwl12y8knvzg62y13jy0lvdzkrari1-neovim-unwrapped-0.11.1/share/nvim
"

Run :checkhealth for more info

Steps to reproduce

nvim --clean test.txt

Expected behavior

Nvim opens test.txt

Nvim version (nvim -v)

0.11.1 Release

Vim (not Nvim) behaves the same?

no, 9.1.1336

Operating system/version

NixOS unstable 2025-05-12; home-manager 2025.05-pre

Terminal name/version

kitty 0.41.1

$TERM environment variable

xterm-kitty

Installation

Nixpkgs through home-manager (programs.nvim.enable = true)