These three lines in ~/.vimrc just changed my life!
let g:netrw_preview = 1
let g:netrw_liststyle = 3
let g:netrw_winsize = 30
and then :Explore works the way it should! Just type “p” to open a file in the preview window and bd or bw to delete a buffer (which doesn’t close the preview window and that’s what I like about it!). Ctrl-W-W to switch between Tree selection and preview window.
:help explore to learn more
The help file is pretty cryptic but it actually helps!