Fix documentation concerning glob expansion on UNIX.

Fixes #4868.

docs/index.md

@@ -2332,9 +2332,12 @@ $ mocha "./spec/**/*.js"
 ```
 
 [You should _always_ quote your globs in npm scripts][article-globbing]. If you
-use double quotes, it's the shell on UNIX that will expand the glob. On the
-other hand, if you use single quotes, the [`node-glob`][npm-glob] module will
-handle its expansion.
+use double quotes or single quotes, the [`node-glob`][npm-glob] module will
+handle its expansion. Single quotes are not supported on Windows, so you should
+avoid them. Note that UNIX shells will perform
+[parameter expansion](https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_02_03)
+within double quotes, so avoid using a dollar sign or backslash in any of your
+paths if you want to support UNIX.
 
 See this [tutorial][gist-globbing-tutorial] on using globs.