diff --git a/components/layout/construct.rs b/components/layout/construct.rs
index 0adde8d7255..efa3ccd176a 100644
--- a/components/layout/construct.rs
+++ b/components/layout/construct.rs
@@ -1533,8 +1533,9 @@ impl<'a, ConcreteThreadSafeLayoutNode> PostorderNodeMutTraversal<ConcreteThreadS
 
         let style = node.style(self.style_context());
 
-        // Bail out if this node has an ancestor with display: none.
-        if style.is_in_display_none_subtree() {
+        // Bail out if this node is display: none. The style system guarantees
+        // that we don't arrive here for children of those.
+        if style.get_box().display.is_none() {
             self.set_flow_construction_result(node, ConstructionResult::None);
             return;
         }
diff --git a/components/layout/display_list/background.rs b/components/layout/display_list/background.rs
index 566752a5499..145c069cb85 100644
--- a/components/layout/display_list/background.rs
+++ b/components/layout/display_list/background.rs
@@ -22,10 +22,11 @@ use style::computed_values::background_origin::single_value::T as BackgroundOrig
 use style::computed_values::border_image_outset::T as BorderImageOutset;
 use style::properties::style_structs::{self, Background};
 use style::values::Either;
-use style::values::computed::{Angle, GradientItem};
+use style::values::computed::{Angle, GradientItem, BackgroundSize as ComputedBackgroundSize};
 use style::values::computed::{LengthOrNumber, LengthOrPercentage, LengthOrPercentageOrAuto};
 use style::values::computed::{NumberOrPercentage, Percentage, Position};
 use style::values::computed::image::{EndingShape, LineDirection};
+use style::values::generics::NonNegative;
 use style::values::generics::background::BackgroundSize;
 use style::values::generics::image::{Circle, Ellipse, ShapeExtent};
 use style::values::generics::image::EndingShape as GenericEndingShape;
@@ -91,7 +92,7 @@ pub fn get_cyclic<T>(arr: &[T], index: usize) -> &T {
 /// For a given area and an image compute how big the
 /// image should be displayed on the background.
 fn compute_background_image_size(
-    bg_size: BackgroundSize<LengthOrPercentageOrAuto>,
+    bg_size: ComputedBackgroundSize,
     bounds_size: Size2D<Au>,
     intrinsic_size: Option<Size2D<Au>>,
 ) -> Size2D<Au> {
@@ -99,9 +100,9 @@ fn compute_background_image_size(
         None => match bg_size {
             BackgroundSize::Cover | BackgroundSize::Contain => bounds_size,
             BackgroundSize::Explicit { width, height } => Size2D::new(
-                MaybeAuto::from_style(width, bounds_size.width)
+                MaybeAuto::from_style(width.0, bounds_size.width)
                     .specified_or_default(bounds_size.width),
-                MaybeAuto::from_style(height, bounds_size.height)
+                MaybeAuto::from_style(height.0, bounds_size.height)
                     .specified_or_default(bounds_size.height),
             ),
         },
@@ -123,29 +124,29 @@ fn compute_background_image_size(
                 (
                     BackgroundSize::Explicit {
                         width,
-                        height: LengthOrPercentageOrAuto::Auto,
+                        height: NonNegative(LengthOrPercentageOrAuto::Auto),
                     },
                     _,
                 ) => {
-                    let width = MaybeAuto::from_style(width, bounds_size.width)
+                    let width = MaybeAuto::from_style(width.0, bounds_size.width)
                         .specified_or_default(own_size.width);
                     Size2D::new(width, width.scale_by(image_aspect_ratio.recip()))
                 },
                 (
                     BackgroundSize::Explicit {
-                        width: LengthOrPercentageOrAuto::Auto,
+                        width: NonNegative(LengthOrPercentageOrAuto::Auto),
                         height,
                     },
                     _,
                 ) => {
-                    let height = MaybeAuto::from_style(height, bounds_size.height)
+                    let height = MaybeAuto::from_style(height.0, bounds_size.height)
                         .specified_or_default(own_size.height);
                     Size2D::new(height.scale_by(image_aspect_ratio), height)
                 },
                 (BackgroundSize::Explicit { width, height }, _) => Size2D::new(
-                    MaybeAuto::from_style(width, bounds_size.width)
+                    MaybeAuto::from_style(width.0, bounds_size.width)
                         .specified_or_default(own_size.width),
-                    MaybeAuto::from_style(height, bounds_size.height)
+                    MaybeAuto::from_style(height.0, bounds_size.height)
                         .specified_or_default(own_size.height),
                 ),
             }
diff --git a/components/layout/display_list/builder.rs b/components/layout/display_list/builder.rs
index b4f8d68282b..a3a40a98cc0 100644
--- a/components/layout/display_list/builder.rs
+++ b/components/layout/display_list/builder.rs
@@ -916,9 +916,9 @@ impl FragmentDisplayListBuilding for Fragment {
                         get_cyclic(&style.get_background().background_size.0, i).clone();
                     let size = match background_size {
                         BackgroundSize::Explicit { width, height } => Size2D::new(
-                            MaybeAuto::from_style(width, bounding_box_size.width)
+                            MaybeAuto::from_style(width.0, bounding_box_size.width)
                                 .specified_or_default(bounding_box_size.width),
-                            MaybeAuto::from_style(height, bounding_box_size.height)
+                            MaybeAuto::from_style(height.0, bounding_box_size.height)
                                 .specified_or_default(bounding_box_size.height),
                         ),
                         _ => bounding_box_size,