commit https://github.com/vim/vim/commit/40b1b5443c88fab77f1f7c6f9e801f7ffdb7e0a8 Author: Bram Moolenaar <Bram@vim.org> Date: Wed Apr 20 20:18:23 2016 +0200 patch 7.4.1759 Problem: When using feedkeys() in a timer the inserted characters are not used right away. Solution: Break the wait loop when characters have been added to typebuf. use this for testing CursorHoldI.

" 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