Don't use autocmd's to select active/inactive statusline

plugin/statusline.lua

@@ -162,25 +162,14 @@ function _G.statusline_inactive()
   return line
 end
 
--- Setup autocmds to set the statusline per buffer.
-local group = vim.api.nvim_create_augroup('statusline', { clear = true })
--- Dynamically update the current buffer mode and color changes using %! to
--- call a function which is always evaluated on statusline update.
-vim.api.nvim_create_autocmd({ 'BufEnter', 'WinEnter', 'BufWinEnter' }, {
-  pattern = '*',
-  group = group,
-  callback = function()
-    vim.cmd.setlocal("statusline=%{%v:lua.statusline_active()%}")
+-- Pick the active or inactive variant for the window currently being drawn.
+function _G.statusline_render()
+  if vim.api.nvim_get_current_win() == tonumber(vim.g.actual_curwin or '-1') then
+    return _G.statusline_active()
+  end
+  return _G.statusline_inactive()
 end
-})
 
--- Statically set the statusline when leaving the buffer.
-vim.api.nvim_create_autocmd({ 'BufLeave', 'WinLeave' }, {
-  pattern = '*',
-  group = group,
-  callback = function()
-    vim.cmd.setlocal("statusline=%{%v:lua.statusline_inactive()%}")
-  end
-})
+vim.o.statusline = '%{%v:lua.statusline_render()%}'
 
 return statusline