How do I create a floating window in Neovim?

Explanation

Neovim's floating windows hover above the main layout, creating popup-like UI elements. They're used by plugins for menus, documentation previews, and notifications. You can create them programmatically using the Neovim API.

How it works

• nvim_open_win(buf, enter, config) — creates a floating window
• buf — buffer to display (0 for current, or create one with nvim_create_buf)
• enter — whether to enter the window (true/false)
• Config options: relative, width, height, row, col, border

Example

:lua local buf = vim.api.nvim_create_buf(false, true)
:lua vim.api.nvim_open_win(buf, true, {
  relative='editor', width=60, height=15,
  row=3, col=10, border='rounded'
})

+---------------------------+
| Main editor               |
|   ╭──────────────────╮    |
|   │ Floating window   │    |
|   │ with border       │    |
|   ╰──────────────────╯    |
+---------------------------+

Tips

• border options: 'none', 'single', 'double', 'rounded', 'shadow'
• Set relative='cursor' to position relative to the cursor
• Close with :q or nvim_win_close(win_id, true)
• Use nvim_create_buf(false, true) for a scratch buffer (unlisted, no swapfile)