I had excellent experience a couple of years ago with WebStorm and Bootstrap 3 projects. - That time I used to have 'css' and 'less' sibling folders in project root and passed to File Watcher the following:
Arguments: '--no-color $FileName$'
Output paths to refresh: '$FileParentDir$\css\$FileNameWithoutExtension$.css'
Nowadays I have the same project structure but prefix '$FileParentDir$\css\' in 'Output paths to refresh' doesn't help: generated *.css and *css.map files live in 'less' folder.
What magic macro prefix shall I use to win File Watcher for 'Less' in PhpStorm 2018.5 ?
Regards / Mike