commit https://github.com/vim/vim/commit/2a67ed83a885e8e65e25498660dae4f34d532c7b Author: Bram Moolenaar <Bram@vim.org> Date: Fri Jun 10 21:52:42 2016 +0200 patch 7.4.1915 Problem: The effect of the PopupMenu autocommand isn't directly visible. Solution: Call gui_update_menus() before displaying the popup menu. (Shane Harper, closs https://github.com/vim/vim/issues/855)

" 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