Selectors groups should work in custom selectors preprocessing

[Machy8]

Describe the problem

These selectors:

[&:hover]{color:blue}
md:hover:{color:blue}

Should work here:

const selectors = {
 selector: `
   [&:hover]{color:blue}
   md:hover:{color:blue}
   
   & + div { margin-right:24px }
`
}

Describe the proposed solution

No idea yet. It can cause syntax issues.

Alternatives considered

Ignore it. The preprocessor syntax is maybe flexible enough.

Importance

nice to have