Neovim syntax files for vimscript break highlighting in Vim

[reneegyllensvaan]

Does this bug happen when you install plugin without vim-polyglot?
(not really applicable since it's vim's runtime files, but it does not happen without vim-polyglot)

Describe the bug:
Polyglot recently started breaking vimscript highlighting for me on vanilla vim. It looks like it changed with the fix for #578, where the vimscript files were swapped for neovim's. These don't seem to work with regular vim, causing unhighlighted command names, and highlighting most function calls in command definitions as errors.

I use Vim8 packages, without a wrapper, as an opt package, that I manually load before setting filetype and syntax.

To Reproduce:
Grab this minimal self-installing vimrc (or just don't load polyglot some other way)

" vim: ft=vim
call system('mkdir -p '.$HOME.'/pack/plugins/opt')
if empty(glob('~/.vim/pack/plugins/opt/polyglot'))
  call system('git clone https://github.com/sheerun/vim-polyglot ~/.vim/pack/plugins/opt/polyglot')
end

if $USE_POLYGLOT == "yes"
  packadd polyglot
end

filetype plugin indent on
syntax on

command! Foo call split(expand('%'), '/')

augroup edcon
  autocmd!
  autocmd FileType special echo expand(':e')

augroup END

Running two vim instances, the one on the left with just vim ~/.vimrc, the other one with USE_POLYGLOT=yes vim ~/.vimrc gives:

[ghifarit53]

I haven't updated my vim plugins for months. Today I updated all of them and realized I got this issue too when editing my vimrc. Also, changing the color of vimOption group seems gave no effect

It looks like this

When normally, it looks like this

[reneegyllensvaan]

@ghifarit53 You can add let g:polyglot_disabled = ['vim.plugin'] to your vimrc before you load vim-polyglot to fall back to the bundled runtime highlighting (which is what it seems like it used previously anyway) as a workaround until this is fixed.

[sheerun]

Thanks. I'll just remove vim syntax from polyglot for now.