bug: indent_blankline not showing current_context_start

[miguelbarao]

Neovim version (nvim -v)

0.9.0

Operating system/version

Ubuntu 22.04.2 LTS

Describe the bug

I'm using indent-blankline.nvim with the following settings:

show_current_context = true,
show_current_context_start = true,

This should highlight the current context and underlines the first line of the context.
It was working before the support for this plugin was added to nightfox. Now it only shows the context guide but not the context_start underline.

Steps To Reproduce

Just use the settings above in indent-blankline.nvim and see that the context_start is not underlined.
A complete configuration is setup below in repro.lua.

Expected Behavior

context start should be underlined.

Repro

-- DO NOT change the paths and don't remove the colorscheme
local root = vim.fn.fnamemodify("./.repro", ":p")

-- set stdpaths to use .repro
for _, name in ipairs({ "config", "data", "state", "cache" }) do
  vim.env[("XDG_%s_HOME"):format(name:upper())] = root .. "/" .. name
end

-- bootstrap lazy
local lazypath = root .. "/plugins/lazy.nvim"
if not vim.loop.fs_stat(lazypath) then
  vim.fn.system({ "git", "clone", "--filter=blob:none", "https://github.com/folke/lazy.nvim.git", lazypath })
end
vim.opt.runtimepath:prepend(lazypath)

-- install plugins
local plugins = {
  {
    "EdenEast/nightfox.nvim",
    lazy = false,
    priority = 10000,
    config = function()
      require("nightfox").setup({})
    end,
  },
  -- add any other plugins here
  {
    'lukas-reineke/indent-blankline.nvim',
    enabled = true,
    event = 'BufWinEnter',
    opts = {
      use_treesitter = true,
      char = '▏',
      context_char = '▏',
      show_first_indent_level = true,
      show_trailing_blankline_indent = true,
      show_end_of_line = true,
      show_current_context = true,
      show_current_context_start = true,
    },
    config = true,
  },
  {
    'nvim-treesitter/nvim-treesitter',
    enabled = true,
    version = false,
    build = ':TSUpdate',
    event = { 'BufReadPost', 'BufNewFile' },
    opts = {
      ensure_installed = { 'python' },
      auto_install = true,
      highlight = { enable = true, additional_vim_regex_highlighting = false },
      indent = { enable = true },                                      -- for the = operator
    },
    config = function(_, opts)
      require('nvim-treesitter.configs').setup(opts)
    end,
  }
}
require("lazy").setup(plugins, {
  root = root .. "/plugins",
})

vim.cmd.colorscheme("nightfox")