On , I learnt ...

Vim-markdown has some useful commands

I use sheerun/vim-polyglot but disable its markdown support in favour of plasticboy/vim-markdown.

" ~/.vimrc

" Disable polyglot's markdown support...
let g:polyglot_disabled = ['markdown']
Plug 'sheerun/vim-polyglot'

" ...so we can use the more sophisticated vim-markdown instead.
Plug 'godlygeek/tabular'
Plug 'plasticboy/vim-markdown'

Why? Because plasticboy/vim-markdown has better support for folding, front-matter and syntax highlighting.

Also, I spotted today that it defines several useful Ex commands:

Will start using these more.