patch 9.0.1036: undo misbehaves when writing from an insert mode mapping Commit: https://github.com/vim/vim/commit/3f8f82772313af9f2417b06651f30988b63e1c96 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Dec 8 21:49:35 2022 +0000 patch 9.0.1036: undo misbehaves when writing from an insert mode mapping Problem: Undo misbehaves when writing from an insert mode mapping. Solution: Sync undo when writing. (closes https://github.com/vim/vim/issues/11674)

" Vim filetype plugin
" Language:	Chatito
" Maintainer:	ObserverOfTime <chronobserver@disroot.org>
" Last Change:	2022 Sep 19

if exists('b:did_ftplugin')
  finish
endif
let b:did_ftplugin = 1

setlocal comments=:#,:// commentstring=#\ %s
" indent of 4 spaces is mandated by the spec
setlocal expandtab softtabstop=4 shiftwidth=4

let b:undo_ftplugin = 'setl com< cms< et< sts< sw<'