diff --git a/components/layout_2020/flexbox/layout.rs b/components/layout_2020/flexbox/layout.rs
index a7a2875a703..caf88955a60 100644
--- a/components/layout_2020/flexbox/layout.rs
+++ b/components/layout_2020/flexbox/layout.rs
@@ -1006,6 +1006,7 @@ impl<'a> FlexItem<'a> {
                         let size = replaced.contents.used_size_as_if_inline_element(
                             flex_context.containing_block,
                             &replaced.style,
+                            None,
                             &pbm,
                         );
                         let cross_size = flex_context.vec2_to_flex_relative(size.clone()).cross;
diff --git a/components/layout_2020/flow/inline.rs b/components/layout_2020/flow/inline.rs
index 740c34cf7c0..df96d0bbd4e 100644
--- a/components/layout_2020/flow/inline.rs
+++ b/components/layout_2020/flow/inline.rs
@@ -573,6 +573,7 @@ fn layout_atomic(
             let size = replaced.contents.used_size_as_if_inline_element(
                 ifc.containing_block,
                 &replaced.style,
+                None,
                 &pbm,
             );
             let fragments = replaced
diff --git a/components/layout_2020/flow/mod.rs b/components/layout_2020/flow/mod.rs
index 11af4147ce0..73630acf7bd 100644
--- a/components/layout_2020/flow/mod.rs
+++ b/components/layout_2020/flow/mod.rs
@@ -581,7 +581,7 @@ fn layout_in_flow_replaced_block_level<'a>(
     replaced: &ReplacedContent,
 ) -> BoxFragment {
     let pbm = style.padding_border_margin(containing_block);
-    let size = replaced.used_size_as_if_inline_element(containing_block, style, &pbm);
+    let size = replaced.used_size_as_if_inline_element(containing_block, style, None, &pbm);
 
     let (margin_inline_start, margin_inline_end) =
         solve_inline_margins_for_in_flow_block_level(containing_block, &pbm, size.inline);
diff --git a/components/layout_2020/positioned.rs b/components/layout_2020/positioned.rs
index 37f2a0fb321..727fa618292 100644
--- a/components/layout_2020/positioned.rs
+++ b/components/layout_2020/positioned.rs
@@ -439,6 +439,7 @@ impl HoistedAbsolutelyPositionedBox {
                 let used_size = replaced.contents.used_size_as_if_inline_element(
                     &containing_block.into(),
                     &replaced.style,
+                    None,
                     &pbm,
                 );
                 Vec2 {
diff --git a/components/layout_2020/replaced.rs b/components/layout_2020/replaced.rs
index 642e83f7905..af4a3c8a62b 100644
--- a/components/layout_2020/replaced.rs
+++ b/components/layout_2020/replaced.rs
@@ -309,13 +309,14 @@ impl ReplacedContent {
         &self,
         containing_block: &ContainingBlock,
         style: &ComputedValues,
+        box_size: Option<Vec2<LengthOrAuto>>,
         pbm: &PaddingBorderMargin,
     ) -> Vec2<Length> {
         let mode = style.writing_mode;
         let intrinsic_size = self.flow_relative_intrinsic_size(style);
         let intrinsic_ratio = self.inline_size_over_block_size_intrinsic_ratio(style);
 
-        let box_size = style.content_box_size(containing_block, &pbm);
+        let box_size = box_size.unwrap_or(style.content_box_size(containing_block, &pbm));
         let max_box_size = style.content_max_box_size(containing_block, &pbm);
         let min_box_size = style
             .content_min_box_size(containing_block, &pbm)