wp-includes/style-engine/class-wp-style-engine-css-rule.php:148Gets the full selector.
string public function get_selector() { return $this->selector; }Introduced in 6.1.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/style-engine/class-wp-style-engine-css-rule.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.