how to hide the margin in nvim

[cubewhy]

These margins are so annoying, is there a way to remove them?

I have tried the following settings, but they don't work

resize_in_steps yes
window_margin_width 0
window_padding_width 0
window_padding_height 0

I either tried the solution in #5733 , but also doesn't work

[rivenirvana]

Those aren't margins, they're excess pixels that can't take up the size of a cell. See https://sw.kovidgoyal.net/kitty/conf/#opt-kitty.placement_strategy

[cubewhy]

Those aren't margins, they're excess pixels that can't take up the size of a cell. See https://sw.kovidgoyal.net/kitty/conf/#opt-kitty.placement_strategy

that makes sense

but is there a way to remove this?

[rivenirvana]

I believe the only way to not have those black areas is to change kitty's bg color to what the tui uses as a bg color when the tui is up. You can do this via a kitty watcher that watches for an envvar set by the tui, but if you're only concerned with neovim, it's simpler to set up autocmds. 1 bound to entering nvim and 1 bound to leaving it, and each sending the appropriate escape codes kitty recognizes to change the bg color. A very simple implementation like this should suffice, add it somewhere early in your config:

local kitty_sync_group = vim.api.nvim_create_augroup('KittyColorSync', { clear = true })

vim.api.nvim_create_autocmd({ 'VimLeavePre', 'VimSuspend' }, {
  group = kitty_sync_group,
  desc = 'Restore default kitty colors',
  callback = function(args)
    io.stderr:write("\x1b]21;background\x07")
  end
})

-- also update kitty's bg on ColorScheme
vim.api.nvim_create_autocmd({ 'VimEnter', 'VimResume', 'ColorScheme' }, {
  group = kitty_sync_group,
  desc = 'Set specified highlight groups as transparent',
  callback = function(args)
    local hl = vim.api.nvim_get_hl(0, { name = "Normal" })
    local rgb_hex = string.format("#%06x", hl.bg)
    io.stderr:write("\x1b]21;background=" .. rgb_hex .. "\x07")
  end
})

3 notes:

• You will still see the black areas again if you do window splits, the excess areas are large enough, and the other splits do not have the same bg color as nvim's. All the windows must have the same bg color.
• This method is a bit inconsistent when using ctrl-z and fg to suspend and bring up nvim to the foreground again, but only rarely, just suspend and fg again till it works. Not sure yet if this is a kitty or neovim issue, or a config issue.
• I'm currently working on a simple neovim plugin for this, which also can be configured for kitty's 8 allowed transparent colors, and accounts for winblends usually used by backdrops of popup menus. I can notify you when it's done if you're interested.

resize_in_steps would be your ideal solution but it currently does not work in Wayland.