patch 8.2.0397: delayed screen update when using undo from Insert mode Commit: https://github.com/vim/vim/commit/5715b3147bfc8ddfe905339f6fd224fd3a5a3ba1 Author: Bram Moolenaar <Bram@vim.org> Date: Mon Mar 16 22:08:45 2020 +0100 patch 8.2.0397: delayed screen update when using undo from Insert mode Problem: Delayed screen update when using undo from Insert mode. Solution: Update w_topline and cursor shape before sleeping. (closes https://github.com/vim/vim/issues/5790)

" Vim filetype plugin
" Language:	Dockerfile
" Maintainer:   Honza Pokorny <http://honza.ca>
" Last Change:	2014 Aug 29

" Only do this when not done yet for this buffer
if exists("b:did_ftplugin")
  finish
endif

" Don't load another plugin for this buffer
let b:did_ftplugin = 1

let b:undo_ftplugin = "setl commentstring<"

setlocal commentstring=#\ %s