patch 8.0.0649: when opening a help file the filetype is set several times commit https://github.com/vim/vim/commit/9049298f8d0bbc237b7c666c7ad6cdabe738e8fc Author: Bram Moolenaar <Bram@vim.org> Date: Thu Jun 22 14:16:31 2017 +0200 patch 8.0.0649: when opening a help file the filetype is set several times Problem: When opening a help file the filetype is set several times. Solution: When setting the filetype to the same value from a modeline, don't trigger FileType autocommands. Don't set the filetype to "help" when it's already set correctly.

" Vim syntax file
" Language:  systemd.unit(5)

if !exists('b:current_syntax')
  " Looks a lot like dosini files.
  runtime! syntax/dosini.vim
  let b:current_syntax = 'systemd'
endif