Problem with tabline on/off (toggle with it bufferline plugin)

[morenohernan]

Context
-------

I'm a newbie with neovim / lazyvim. I want to have the possibility to toggle on/off buffer tabs (I'm using bufferline plugin). So far I have this script(see below). In this way lazyvim starts with no tabline and by hitting bt I can toggle on/off tabs to see my buffers.

Problem
--------
Every time I save a file, if the tabline is disabled somehow it gets enabled. But this is not the behaviour I want, I just want to toggle it on/off only when I use the proper keystrokes(bt).

autocmds.lua
-------------

-- Disable tabline by default at startup
vim.api.nvim_create_autocmd("BufReadPre", {
  group = vim.api.nvim_create_augroup("showtabline", { clear = true }),
  callback = function()
    vim.opt.showtabline = 0
  end,
  desc = "Set tabline to 0 / Disable tabline",
})

in plugins folder (bufferline.lua)
----------------------------------
  -- Custom code to toggle tabline
_G.toggle_tabline = function()
    local showtabline = vim.api.nvim_get_option("showtabline")
    if showtabline > 0 then
        vim.api.nvim_set_option("showtabline", 0) -- disable tabline
    else
        vim.api.nvim_set_option("showtabline", 2) -- always show tabline
    end
end

vim.cmd("command! ToggleTabline lua toggle_tabline()")

  return {
  "akinsho/bufferline.nvim",
  enabled = true,
  keys = function()
    return {
      { "<leader>bp", "<Cmd>BufferLineTogglePin<CR>", desc = "Toggle pin on current buffer" },
      { "<leader>bt", "<cmd>ToggleTabline<cr>", desc = "Toggle buffer tabline" },
      {"<leader>bse", "<cmd>BufferLineSortByExtension<cr>", desc = "Sort buffers by extension"},
      {"<leader>bsd", "<cmd>BufferLineSortByDirectory<cr>", desc = "Sort buffers by directory" },
      {"<leader>bst", "<cmd>BufferLineSortByTabs<cr>", desc = "Sort buffers by tabs" },

      { "<leader>bdn", "<Cmd>BufferLineGroupClose ungrouped<CR>", desc = "Delete non-pinned buffers" },
      {"<leader>bdr", "<cmd>BufferLineCloseRight<cr>", desc = "Delete buffers to the right from current" },
      {"<leader>bdl", "<cmd>BufferLineCloseLeft<cr>", desc = "Delete buffers to the left from current" },
      {"<leader>bdo", "<cmd>BufferLineCloseOthers<cr>", desc = "Delete buffers others than current" },      
    }
  end,  
  opts = {
    options = {
      show_buffer_close_icons = false,
      show_tab_indicators = false,
      always_show_bufferline = false,
      offsets = {
        {
          filetype = "neo-tree",
          text = "File Explorer",
          highlight = "Directory",
          text_align = "left",
        },
      },
      hover = {
          enabled = true,
          delay = 200,
          reveal = {'close'}
      },
    },
  },
}

[abeldekat]

See the discussion in LazyVim