diff --git a/src/selector/extend/extension.rs b/src/selector/extend/extension.rs
index 54f188f..e4e5e12 100644
--- a/src/selector/extend/extension.rs
+++ b/src/selector/extend/extension.rs
@@ -2,7 +2,7 @@ use codemap::Span;
 
 use super::{ComplexSelector, CssMediaQuery, SimpleSelector};
 
-#[derive(Clone, Debug, Eq, PartialEq, Hash)]
+#[derive(Clone, Debug)]
 pub(crate) struct Extension {
     /// The selector in which the `@extend` appeared.
     pub extender: ComplexSelector,
diff --git a/src/selector/extend/mod.rs b/src/selector/extend/mod.rs
index 68b236e..ee87a2a 100644
--- a/src/selector/extend/mod.rs
+++ b/src/selector/extend/mod.rs
@@ -55,7 +55,7 @@ impl Default for ExtendMode {
     }
 }
 
-#[derive(Clone, Debug, Eq, PartialEq)]
+#[derive(Clone, Debug)]
 pub(crate) struct Extender {
     /// A map from all simple selectors in the stylesheet to the selector lists
     /// that contain them.
diff --git a/src/selector/extend/rule.rs b/src/selector/extend/rule.rs
index 8a1749e..f0d7a69 100644
--- a/src/selector/extend/rule.rs
+++ b/src/selector/extend/rule.rs
@@ -2,7 +2,7 @@ use codemap::Span;
 
 use crate::selector::Selector;
 
-#[derive(Clone, Debug, Eq, PartialEq)]
+#[derive(Clone, Debug)]
 pub(crate) struct ExtendRule {
     pub selector: Selector,
     pub is_optional: bool,
diff --git a/src/selector/list.rs b/src/selector/list.rs
index 7000fae..813c4f3 100644
--- a/src/selector/list.rs
+++ b/src/selector/list.rs
@@ -1,6 +1,7 @@
 use std::{
     collections::VecDeque,
     fmt::{self, Write},
+    hash::{Hash, Hasher},
     mem,
 };
 
@@ -18,7 +19,7 @@ use crate::{
 ///
 /// A selector list is composed of `ComplexSelector`s. It matches an element
 /// that matches any of the component selectors.
-#[derive(Clone, Debug, Eq, PartialEq, Hash)]
+#[derive(Clone, Debug)]
 pub(crate) struct SelectorList {
     /// The components of this selector.
     ///
@@ -27,6 +28,20 @@ pub(crate) struct SelectorList {
     pub span: Span,
 }
 
+impl PartialEq for SelectorList {
+    fn eq(&self, other: &SelectorList) -> bool {
+        self.components == other.components
+    }
+}
+
+impl Eq for SelectorList {}
+
+impl Hash for SelectorList {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.components.hash(state);
+    }
+}
+
 impl fmt::Display for SelectorList {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         let complexes = self.components.iter().filter(|c| !c.is_invisible());