Diffthis does not work

[ysooqe]

Hi there, amazing plugin! Unfortunately I am a little lost with diffthis and would like to ask for help.
I can not get diffthis to work. When I call the command, nothing happens.
My setup:

# nvim version
NVIM v0.11.4
Build type: RelWithDebInfo
LuaJIT 2.1.1753364724

# git version
git version 2.51.1.dirty

-- ~/.config/nvim/lua/plugins/gitsigns.lua
return {
  'lewis6991/gitsigns.nvim',
  version = '*',
  opts = {
    signs = {
      delete = { show_count = true },
      topdelete = { show_count = true },
      changedelete = { show_count = true },
    },
    signs_staged = {
      delete = { show_count = true },
      topdelete = { show_count = true },
      changedelete = { show_count = true },
    },
    current_line_blame_opts = {
      virt_text_pos = 'right_align',
      delay = 0,
      virt_text_priority = 100,
    },
    current_line_blame_formatter = '<abbrev_sha> | <author>, <author_time:%R> - <summary>',
    update_debounce = 0,
  },
  keys = function()
    local bufnr = vim.api.nvim_get_current_buf()
    local gitsigns = require('gitsigns')
    return {
      {
        '<leader>gl',
        gitsigns.toggle_linehl,
        desc = '[t]oggle linehl',
        buffer = bufnr,
      },
      {
        '<leader>gd',
        gitsigns.diffthis,
        desc = '[d]iff this',
        buffer = bufnr,
      },
      {
        '<leader>gD',
        function() gitsigns.diffthis('~') end,
        desc = '[D]iff this (~)',
        buffer = bufnr,
      },
    }
  end,
}

I have a file that is tracked in git by multiple commits. When I make some changes to the file (not staged, changes are still only in the worktree) and then call :Gitsigns diffthis (or the keybinding from above), I expected that a vimdiff buffer would open with the current changes compared to index (index currently represents the previous commit since changes are not yet staged), but nothing happens. There is also no hidden buffer (:ls!).
Calling :Gitsigns diffthis ~2 (or with any other revision) also does not work.

What am I doing wrong or what am I missing here?

[ysooqe]

I have "solved" the issue, I think.
I commented out the version in the plugin config and installed the plugin from the latest commit. Calling :Gitsigns diffthis yielded an error message that indicated an improperly configured autocmd somewhere else in my config. I fixed the autocmd and now :Gitsigns diffthis works as expected.