commit https://github.com/vim/vim/commit/1610d052413e0ed664498853a47acc2d677a22d1 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Jun 9 22:53:01 2016 +0200 patch 7.4.1913 Problem: When ":doautocmd" is used modelines are used even when no autocommands were executed. (Daniel Hahler) Solution: Skip processing modelines. (closes https://github.com/vim/vim/issues/854)

" Vim filetype plugin file
" Language:	Diff
" Maintainer:	Bram Moolenaar <Bram@vim.org>
" Last Change:	2005 Jul 27

" Only do this when not done yet for this buffer
if exists("b:did_ftplugin")
  finish
endif
let b:did_ftplugin = 1

let b:undo_ftplugin = "setl modeline<"

" Don't use modelines in a diff, they apply to the diffed file
setlocal nomodeline