commit https://github.com/vim/vim/commit/19ff9bf454b7492be64dd87aaf0830fa7961871e Author: Bram Moolenaar <Bram@vim.org> Date: Sun Jul 10 19:03:57 2016 +0200 patch 7.4.2021 Problem: Still too many buf_valid() calls. Solution: Make au_new_curbuf a bufref. Use bufref_valid() in more places.

" For Yiddish capitals should not be checked.  But only change the
" 'spellcapcheck' option when it is not at its default value.
let s:spc = &l:spc
setlocal spc&
if s:spc == &l:spc
  setlocal spc=
else
  let &l:spc = s:spc
endif
unlet s:spc