diff --git a/servo/components/style/build.rs b/servo/components/style/build.rs
index 517c65f99dc2..76118da42123 100644
--- a/servo/components/style/build.rs
+++ b/servo/components/style/build.rs
@@ -76,16 +76,6 @@ fn generate_properties() {
         .arg(&script)
         .arg(product)
         .arg("style-crate")
-        .envs(if std::mem::size_of::<Option<bool>>() == 1 {
-            // FIXME: remove this envs() call
-            // and make unconditional code that depends on RUSTC_HAS_PR45225
-            // once Firefox requires Rust 1.23+
-
-            // https://github.com/rust-lang/rust/pull/45225
-            vec![("RUSTC_HAS_PR45225", "1")]
-        } else {
-            vec![]
-        })
         .status()
         .unwrap();
     if !status.success() {
diff --git a/servo/components/style/properties/build.py b/servo/components/style/properties/build.py
index 4ffdd6a6df52..326859ea6d81 100644
--- a/servo/components/style/properties/build.py
+++ b/servo/components/style/properties/build.py
@@ -32,8 +32,7 @@ def main():
 
     properties = data.PropertiesData(product=product)
     template = os.path.join(BASE, "properties.mako.rs")
-    rust = render(template, product=product, data=properties, __file__=template,
-                  RUSTC_HAS_PR45225=os.environ.get("RUSTC_HAS_PR45225"))
+    rust = render(template, product=product, data=properties, __file__=template)
     if output == "style-crate":
         write(os.environ["OUT_DIR"], "properties.rs", rust)
         if product == "gecko":
diff --git a/servo/components/style/properties/longhand/inherited_svg.mako.rs b/servo/components/style/properties/longhand/inherited_svg.mako.rs
index f03d6a8acee8..9e341e8b7c8b 100644
--- a/servo/components/style/properties/longhand/inherited_svg.mako.rs
+++ b/servo/components/style/properties/longhand/inherited_svg.mako.rs
@@ -66,9 +66,9 @@ ${helpers.predefined_type(
     "stroke-width", "SVGWidth",
     "::values::computed::NonNegativeLength::new(1.).into()",
     products="gecko",
-    boxed=not RUSTC_HAS_PR45225,
     animation_value_type="::values::computed::SVGWidth",
-    spec="https://www.w3.org/TR/SVG2/painting.html#StrokeWidth")}
+    spec="https://www.w3.org/TR/SVG2/painting.html#StrokeWidth",
+)}
 
 ${helpers.single_keyword("stroke-linecap", "butt round square",
                          products="gecko", animation_value_type="discrete",
@@ -101,9 +101,9 @@ ${helpers.predefined_type(
     "stroke-dashoffset", "SVGLength",
     "Au(0).into()",
     products="gecko",
-    boxed=not RUSTC_HAS_PR45225,
     animation_value_type="ComputedValue",
-    spec="https://www.w3.org/TR/SVG2/painting.html#StrokeDashing")}
+    spec="https://www.w3.org/TR/SVG2/painting.html#StrokeDashing",
+)}
 
 // Section 14 - Clipping, Masking and Compositing
 ${helpers.single_keyword("clip-rule", "nonzero evenodd",
diff --git a/servo/components/style/properties/longhand/pointing.mako.rs b/servo/components/style/properties/longhand/pointing.mako.rs
index 3b8957491160..6dbb71c59aeb 100644
--- a/servo/components/style/properties/longhand/pointing.mako.rs
+++ b/servo/components/style/properties/longhand/pointing.mako.rs
@@ -47,7 +47,6 @@ ${helpers.predefined_type(
     "generics::pointing::CaretColor::Auto",
     spec="https://drafts.csswg.org/css-ui/#caret-color",
     animation_value_type="AnimatedCaretColor",
-    boxed=not RUSTC_HAS_PR45225,
     ignored_when_colors_disabled=True,
     products="gecko",
 )}
diff --git a/servo/geckolib-rust-toolchain b/servo/geckolib-rust-toolchain
index a6c2798a482e..53cc1a6f9292 100644
--- a/servo/geckolib-rust-toolchain
+++ b/servo/geckolib-rust-toolchain
@@ -1 +1 @@
-1.23.0
+1.24.0