diff --git a/Userland/Libraries/LibWeb/Layout/FormattingContext.cpp b/Userland/Libraries/LibWeb/Layout/FormattingContext.cpp
index 2a08e9f126..8da09790a7 100644
--- a/Userland/Libraries/LibWeb/Layout/FormattingContext.cpp
+++ b/Userland/Libraries/LibWeb/Layout/FormattingContext.cpp
@@ -1111,13 +1111,22 @@ float FormattingContext::containing_block_height_for(Box const& box, LayoutState
     VERIFY_NOT_REACHED();
 }
 
+static Box const* previous_block_level_sibling(Box const& box)
+{
+    for (auto* sibling = box.previous_sibling_of_type<Box>(); sibling; sibling = sibling->previous_sibling_of_type<Box>()) {
+        if (sibling->computed_values().display().is_block_outside())
+            return sibling;
+    }
+    return nullptr;
+}
+
 float FormattingContext::compute_box_y_position_with_respect_to_siblings(Box const& child_box, LayoutState::UsedValues const& box_state)
 {
     float y = box_state.border_box_top();
 
     Vector<float> collapsible_margins;
 
-    auto* relevant_sibling = child_box.previous_sibling_of_type<Layout::BlockContainer>();
+    auto* relevant_sibling = previous_block_level_sibling(child_box);
     while (relevant_sibling != nullptr) {
         if (!relevant_sibling->is_absolutely_positioned() && !relevant_sibling->is_floating()) {
             auto const& relevant_sibling_state = m_state.get(*relevant_sibling);
@@ -1127,7 +1136,7 @@ float FormattingContext::compute_box_y_position_with_respect_to_siblings(Box con
                 break;
             collapsible_margins.append(relevant_sibling_state.margin_top);
         }
-        relevant_sibling = relevant_sibling->previous_sibling_of_type<Layout::BlockContainer>();
+        relevant_sibling = previous_block_level_sibling(*relevant_sibling);
     }
 
     if (relevant_sibling) {