Originally reported at: https://github.com/vim-jp/issues/issues/1428
'isk' was unintentionally changed by netrw, regression
introduced in Commit: 71badf9547e8f89571b9a095183671cbb333d528
Signed-off-by: Ken Takata <kentkt@csc.jp>
Signed-off-by: Christian Brabandt <cb@256bit.org>