Neovim true color support - Color name or number not recognized

[rafalio]

I'm running Neovim with true color enabled (let $NVIM_TUI_ENABLE_TRUE_COLOR=1) and getting the following error with vim-pandoc-syntax:

line  596:
E421: Color name or number not recognized: ctermfg=#b8bb26

It looks like this is similar to this issue: junegunn/goyo.vim#92

[fmoralesc]

You probably need to add set termguicolors instead of setting the env var.

[zaript]

I confirm, that the issue is resolved in unstable neovim.

As it says here:
2016/05/11
"True color" support now requires set termguicolors in your init.vim. NVIM_TUI_ENABLE_TRUE_COLOR is ignored. #4690