diff --git a/components/layout/block.rs b/components/layout/block.rs
index ed442ece5465..c92c79122bd4 100644
--- a/components/layout/block.rs
+++ b/components/layout/block.rs
@@ -978,13 +978,15 @@ impl BlockFlow {
// root element as having `overflow: scroll` and use the layers-based scrolling
// infrastructure to make it scrollable.
let mut block_size = cur_b - block_start_offset;
- if self.is_root() {
+ let is_root = self.is_root();
+ if is_root {
let screen_size = LogicalSize::from_physical(
self.fragment.style.writing_mode, layout_context.shared.screen_size);
block_size = Au::max(screen_size.block, block_size)
}
- if self.is_float() || self.is_absolutely_positioned() {
+ if is_root || self.formatting_context_type() != NonformattingContext ||
+ self.is_absolutely_positioned() {
// The content block-size includes all the floats per CSS 2.1 ยง 10.6.7. The easiest way
// to handle this is to just treat this as clearance.
block_size = block_size + floats.clearance(ClearBoth);
diff --git a/tests/ref/basic.list b/tests/ref/basic.list
index c342c3bec9c4..9ed06cd99d7a 100644
--- a/tests/ref/basic.list
+++ b/tests/ref/basic.list
@@ -147,3 +147,4 @@ flaky_gpu,flaky_linux == acid2_noscroll.html acid2_ref_broken.html
== floated_table_with_margin_a.html floated_table_with_margin_ref.html
== margins_inside_floats_a.html margins_inside_floats_ref.html
== block_formatting_context_complex_a.html block_formatting_context_complex_ref.html
+== block_formatting_context_containing_floats_a.html block_formatting_context_containing_floats_ref.html
diff --git a/tests/ref/block_formatting_context_containing_floats_a.html b/tests/ref/block_formatting_context_containing_floats_a.html
new file mode 100644
index 000000000000..41666502b75f
--- /dev/null
+++ b/tests/ref/block_formatting_context_containing_floats_a.html
@@ -0,0 +1,9 @@
+
+
+
+
+
+
+
diff --git a/tests/ref/block_formatting_context_containing_floats_ref.html b/tests/ref/block_formatting_context_containing_floats_ref.html
new file mode 100644
index 000000000000..51dfab031eb6
--- /dev/null
+++ b/tests/ref/block_formatting_context_containing_floats_ref.html
@@ -0,0 +1,10 @@
+
+
+
+