g:netrw_altfile = 1 doesn't work as expected for files in subdirectories

[smlx]

Hi, first thanks for the great plugin. It's a real game changer for my workflows and has worked well for years.

I've recently found that let g:netrw_altfile = 1 doesn't work as expected with vim-vinegar. However it does work for :Explore! Let me give some scenarios to explain.

Assume I am in a directory with a subdirectory subdir containing file1, and file2. let g:netrw_altfile = 1 is set.

Scenario 1 (:Explore works as expected):

1. nvim subdir/file1 to open file1.
2. :Explore to open netrw.
3. Select file2 and hit enter to open it.
4. Ctrl-6 takes me back to file1.

Scenario 2 (vim-vinegar doesn't work as expected):

1. nvim subdir/file1 to open file1.
2. - in normal mode to open netrw via vim-vinegar.
3. Select file2 and hit enter to open it.
4. Ctrl-6 takes me back to netrw.

I would expect that with g:netrw_altfile = 1 set, step 4 in Scenario 2 should take me back to file1.

Interestingly, if I am running nvim from the subdirectory containing the files then vim-vinegar works the same way as :Explore (i.e. as I would expect).

I'm using Neovim v0.10.0, and vim-vinegar bb1bcddf43cfebe05eb565a84ab069b357d0b3d6.