What does `@<Plug>` mean in a mapping?

Question

I have vimwiki and vim-vinegar and they conflict on an nmap. Calling map - shows these two maps:

n  -            @<Plug>VimwikiRemoveHeaderLevel
n  -             <Plug>VinegarUp

unmap only removed the vinegar map, and subsequent unmaps didn't touch the other map. What I actually wanted to is to unmap the vimwiki map. What does the @ mean in front of <Plug>? How can I remove a mapping like that? Could I specifically unmap just this one map?

Answer 1

Try :help map-listing, so we know @ signifies a buffer-local mapping (<Plug> is its own thing: :help <Plug>).

To unmap a buffer-local mapping, you have to pass <buffer>: :nunmap <buffer> - (:help map-buffer).