bug: lazy window backdrop doesn't disappear when closing in plugin setup

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Neovim version (nvim -v)

NVIM v0.10.0-dev-2702+g0c0be09ea-dirty

Operating system/version

Arch Linux

Describe the bug

On startup, Lazy opens when plugins are missing. I have a plugin spec (for dashboard-nvim) which closes the window if it's open. It doesn't clear the backdrop when closing.

Steps To Reproduce

nvim -nu repro.lua
Clean nvim-treesitter (any plugin) (the repro does this for you)
Open nvim
Wait for it to install
Notice darkened editor

Expected Behavior

Remove the backdrop on close

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 = {
  "folke/tokyonight.nvim",
  { "nvim-treesitter/nvim-treesitter" }, -- Any plugin works, just need something to cause lazy to open
  {
    "echasnovski/mini.animate", -- any plugin, just using for `event =`
    event = "VimEnter", -- This doesn't work as a normal autocmd. I don't know why.
    opts = function()
      if vim.o.filetype == "lazy" then
        vim.cmd.close()
      end
    end,
  },
}
require("lazy").setup(plugins, { install = { colorscheme = { "tokyonight-night" } } }) -- It's more obvious with tokyonight
require("lazy").clean({ plugins = { "nvim-treesitter" }, show = false }) -- Make repro easier by making this idempotent

folke / lazy.nvim

bug: lazy window backdrop doesn't disappear when closing in plugin setup #1390