To reproduce:
a:is(.b, :is(.c)) {
color: blue;
}
Current behavior:
Reports Missing closing ')' even though parentheses are balanced. This is true for :is(), :where(), and :not() which all can accept selector lists, meaning those selector lists may also have :is(), :where(), and :not(). It's possible that those pseudo-selectors are not parsing their contents as selectors.
Expected behavior:
Selectors should support nesting of selectors within pseudo-selectors that take relative selector lists as input
Environment information:
less version: 4.2.0
nodejs version: Current Less preview
operating system: