diff --git a/components/layout/Cargo.toml b/components/layout/Cargo.toml
index 93c8045b70c..26908836b5f 100644
--- a/components/layout/Cargo.toml
+++ b/components/layout/Cargo.toml
@@ -64,7 +64,7 @@ heapsize_plugin = "0.1.2"
 libc = "0.2"
 log = "0.3"
 rustc-serialize = "0.3"
-selectors = {version = "0.4.1", features = ["heap_size"]}
+selectors = {version = "0.4.2", features = ["heap_size"]}
 serde = "0.6"
 serde_json = "0.5"
 serde_macros = "0.6"
diff --git a/components/script/Cargo.toml b/components/script/Cargo.toml
index f9ddac1df14..cb387cbb753 100644
--- a/components/script/Cargo.toml
+++ b/components/script/Cargo.toml
@@ -81,7 +81,7 @@ num = "0.1.24"
 rand = "0.3"
 ref_slice = "0.1.0"
 rustc-serialize = "0.3"
-selectors = {version = "0.4.1", features = ["heap_size"]}
+selectors = {version = "0.4.2", features = ["heap_size"]}
 serde = "0.6"
 smallvec = "0.1"
 string_cache = {version = "0.2.9", features = ["heap_size", "unstable"]}
diff --git a/components/servo/Cargo.lock b/components/servo/Cargo.lock
index 90d21b7110a..6ab955bb7c5 100644
--- a/components/servo/Cargo.lock
+++ b/components/servo/Cargo.lock
@@ -1006,7 +1006,7 @@ dependencies = [
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "script 0.0.1",
  "script_traits 0.0.1",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1593,7 +1593,7 @@ dependencies = [
  "ref_slice 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "script_traits 0.0.1",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "string_cache 0.2.9 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1644,7 +1644,7 @@ dependencies = [
 
 [[package]]
 name = "selectors"
-version = "0.4.1"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1853,7 +1853,7 @@ dependencies = [
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
  "plugins 0.0.1",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1873,7 +1873,7 @@ dependencies = [
  "euclid 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "msg 0.0.1",
  "plugins 0.0.1",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "string_cache 0.2.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "style_traits 0.0.1",
@@ -1894,7 +1894,7 @@ dependencies = [
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
  "plugins 0.0.1",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2052,7 +2052,7 @@ dependencies = [
  "plugins 0.0.1",
  "rand 0.3.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/components/style/Cargo.toml b/components/style/Cargo.toml
index d66d093b98d..d7cd5790e08 100644
--- a/components/style/Cargo.toml
+++ b/components/style/Cargo.toml
@@ -32,7 +32,7 @@ log = "0.3"
 matches = "0.1"
 num = "0.1.24"
 rustc-serialize = "0.3"
-selectors = {version = "0.4.1", features = ["heap_size", "unstable"]}
+selectors = {version = "0.4.2", features = ["heap_size", "unstable"]}
 serde = "0.6"
 serde_macros = "0.6"
 smallvec = "0.1"
diff --git a/components/style_traits/Cargo.toml b/components/style_traits/Cargo.toml
index efb1bf2cb19..e7c7f953bf0 100644
--- a/components/style_traits/Cargo.toml
+++ b/components/style_traits/Cargo.toml
@@ -22,7 +22,7 @@ lazy_static = "0.1.10"
 log = "0.3"
 num = "0.1.24"
 rustc-serialize = "0.3"
-selectors = {version = "0.4.1", features = ["heap_size"]}
+selectors = {version = "0.4.2", features = ["heap_size"]}
 serde = "0.6"
 serde_macros = "0.6"
 url = {version = "0.5.4", features = ["heap_size"]}
diff --git a/components/util/Cargo.toml b/components/util/Cargo.toml
index 77bed3815ce..e2a6016b963 100644
--- a/components/util/Cargo.toml
+++ b/components/util/Cargo.toml
@@ -41,7 +41,7 @@ num = "0.1.24"
 num_cpus = "0.2.2"
 rand = "0.3"
 rustc-serialize = "0.3"
-selectors = {version = "0.4.1", features = ["heap_size"]}
+selectors = {version = "0.4.2", features = ["heap_size"]}
 serde = "0.6"
 serde_macros = "0.6"
 smallvec = "0.1"
diff --git a/ports/cef/Cargo.lock b/ports/cef/Cargo.lock
index 5fd8769bd90..2707508caa7 100644
--- a/ports/cef/Cargo.lock
+++ b/ports/cef/Cargo.lock
@@ -937,7 +937,7 @@ dependencies = [
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "script 0.0.1",
  "script_traits 0.0.1",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1480,7 +1480,7 @@ dependencies = [
  "ref_slice 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "script_traits 0.0.1",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "string_cache 0.2.9 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1522,7 +1522,7 @@ dependencies = [
 
 [[package]]
 name = "selectors"
-version = "0.4.1"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1766,7 +1766,7 @@ dependencies = [
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
  "plugins 0.0.1",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1790,7 +1790,7 @@ dependencies = [
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
  "plugins 0.0.1",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1948,7 +1948,7 @@ dependencies = [
  "plugins 0.0.1",
  "rand 0.3.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/ports/geckolib/Cargo.lock b/ports/geckolib/Cargo.lock
index f290c3abbe8..35a2c19a0d9 100644
--- a/ports/geckolib/Cargo.lock
+++ b/ports/geckolib/Cargo.lock
@@ -9,7 +9,7 @@ dependencies = [
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "string_cache 0.2.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
@@ -315,7 +315,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "selectors"
-version = "0.4.1"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -392,7 +392,7 @@ dependencies = [
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
  "plugins 0.0.1",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -416,7 +416,7 @@ dependencies = [
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
  "plugins 0.0.1",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -495,7 +495,7 @@ dependencies = [
  "plugins 0.0.1",
  "rand 0.3.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/ports/geckolib/Cargo.toml b/ports/geckolib/Cargo.toml
index 2b306a25c13..ff313b36d05 100644
--- a/ports/geckolib/Cargo.toml
+++ b/ports/geckolib/Cargo.toml
@@ -16,7 +16,7 @@ euclid = {version = "0.6.2", features = ["plugins"]}
 libc = "0.2"
 log = "0.3"
 num_cpus = "0.2.2"
-selectors = {version = "0.4.1", features = ["heap_size"]}
+selectors = {version = "0.4.2", features = ["heap_size"]}
 smallvec = "0.1"
 string_cache = {version = "0.2.9", features = ["heap_size"]}
 url = {version = "0.5.4", features = ["heap_size"]}
diff --git a/ports/gonk/Cargo.lock b/ports/gonk/Cargo.lock
index e31024523cc..0a667fe607b 100644
--- a/ports/gonk/Cargo.lock
+++ b/ports/gonk/Cargo.lock
@@ -919,7 +919,7 @@ dependencies = [
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "script 0.0.1",
  "script_traits 0.0.1",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1462,7 +1462,7 @@ dependencies = [
  "ref_slice 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "script_traits 0.0.1",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "string_cache 0.2.9 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1504,7 +1504,7 @@ dependencies = [
 
 [[package]]
 name = "selectors"
-version = "0.4.1"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1746,7 +1746,7 @@ dependencies = [
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
  "plugins 0.0.1",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1770,7 +1770,7 @@ dependencies = [
  "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
  "plugins 0.0.1",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1928,7 +1928,7 @@ dependencies = [
  "plugins 0.0.1",
  "rand 0.3.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.16 (registry+https://github.com/rust-lang/crates.io-index)",
- "selectors 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "selectors 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/tests/unit/style/Cargo.toml b/tests/unit/style/Cargo.toml
index 0f2fabf431a..8c173420329 100644
--- a/tests/unit/style/Cargo.toml
+++ b/tests/unit/style/Cargo.toml
@@ -27,6 +27,6 @@ path = "../../../components/util"
 app_units = {version = "0.2.1", features = ["plugins"]}
 cssparser = {version = "0.5.3", features = ["heap_size"]}
 euclid = {version = "0.6.2", features = ["plugins"]}
-selectors = {version = "0.4.1", features = ["heap_size"]}
+selectors = {version = "0.4.2", features = ["heap_size"]}
 string_cache = {version = "0.2.9", features = ["heap_size"]}
 url = {version = "0.5.4", features = ["heap_size"]}