There is a note saying this:
But both package are in conflicts:
pikaur -S powerline-fonts-git Reading repository package databases... Reading local package database... Resolving AUR dependencies... :: AUR package will be installed: powerline-fonts-git -> r100.a44abd0-3 :: Proceed with installation? [Y/n] :: [v]iew package details [m]anually select packages >> y looking for conflicting AUR packages... :: powerline-fonts-git and powerline-fonts are in conflict. Remove powerline-fonts? [y/N] N
It's not clear from the page that Neovim is currently not supported, as reported here: https://github.com/powerline/powerline/issues/1287.
Also the "vim plugin manager" installation says "or ~/.local/share/nvim/plugged for Neovim".
I think any current mention of Neovim should be removed and a note explicitly saying that Neovim is not supported added.