From 4eb16b144e20d615db2febaa42c78e89ecbc3e24 Mon Sep 17 00:00:00 2001
From: Aliaksandr Kalenik <kalenik.aliaksandr@gmail.com>
Date: Wed, 11 Sep 2024 01:14:56 +0200
Subject: [PATCH] LibWeb: Skip abspos boxes layout in intrinsic sizing mode

Absolutely positioned boxes do not affect the size of the formatting
context box they belong to, so it's safe to skip their layout entirely
when calculating intrinsic size.
---
 .../LibWeb/Layout/BlockFormattingContext.cpp       | 14 ++++++++------
 .../LibWeb/Layout/FlexFormattingContext.cpp        |  3 +++
 .../LibWeb/Layout/GridFormattingContext.cpp        |  3 +++
 3 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/Userland/Libraries/LibWeb/Layout/BlockFormattingContext.cpp b/Userland/Libraries/LibWeb/Layout/BlockFormattingContext.cpp
index e2e89fd48e..485c17d299 100644
--- a/Userland/Libraries/LibWeb/Layout/BlockFormattingContext.cpp
+++ b/Userland/Libraries/LibWeb/Layout/BlockFormattingContext.cpp
@@ -108,12 +108,14 @@ void BlockFormattingContext::parent_context_did_dimension_child_root_box()
         box_state.set_content_x(float_containing_block_width - floating_box->offset_from_edge);
     }
 
-    // We can also layout absolutely positioned boxes within this BFC.
-    for (auto& box : m_absolutely_positioned_boxes) {
-        auto& cb_state = m_state.get(*box->containing_block());
-        auto available_width = AvailableSize::make_definite(cb_state.content_width() + cb_state.padding_left + cb_state.padding_right);
-        auto available_height = AvailableSize::make_definite(cb_state.content_height() + cb_state.padding_top + cb_state.padding_bottom);
-        layout_absolutely_positioned_element(box, AvailableSpace(available_width, available_height));
+    if (m_layout_mode == LayoutMode::Normal) {
+        // We can also layout absolutely positioned boxes within this BFC.
+        for (auto& box : m_absolutely_positioned_boxes) {
+            auto& cb_state = m_state.get(*box->containing_block());
+            auto available_width = AvailableSize::make_definite(cb_state.content_width() + cb_state.padding_left + cb_state.padding_right);
+            auto available_height = AvailableSize::make_definite(cb_state.content_height() + cb_state.padding_top + cb_state.padding_bottom);
+            layout_absolutely_positioned_element(box, AvailableSpace(available_width, available_height));
+        }
     }
 }
 
diff --git a/Userland/Libraries/LibWeb/Layout/FlexFormattingContext.cpp b/Userland/Libraries/LibWeb/Layout/FlexFormattingContext.cpp
index eeaf75e6f1..5f9e163caa 100644
--- a/Userland/Libraries/LibWeb/Layout/FlexFormattingContext.cpp
+++ b/Userland/Libraries/LibWeb/Layout/FlexFormattingContext.cpp
@@ -181,6 +181,9 @@ void FlexFormattingContext::run(AvailableSpace const& available_space)
 
 void FlexFormattingContext::parent_context_did_dimension_child_root_box()
 {
+    if (m_layout_mode != LayoutMode::Normal)
+        return;
+
     flex_container().for_each_child_of_type<Box>([&](Layout::Box& box) {
         if (box.is_absolutely_positioned()) {
             auto& cb_state = m_state.get(*box.containing_block());
diff --git a/Userland/Libraries/LibWeb/Layout/GridFormattingContext.cpp b/Userland/Libraries/LibWeb/Layout/GridFormattingContext.cpp
index dda7e706aa..09102dec19 100644
--- a/Userland/Libraries/LibWeb/Layout/GridFormattingContext.cpp
+++ b/Userland/Libraries/LibWeb/Layout/GridFormattingContext.cpp
@@ -2005,6 +2005,9 @@ void GridFormattingContext::layout_absolutely_positioned_element(Box const& box,
 
 void GridFormattingContext::parent_context_did_dimension_child_root_box()
 {
+    if (m_layout_mode != LayoutMode::Normal)
+        return;
+
     grid_container().for_each_child_of_type<Box>([&](Layout::Box& box) {
         if (box.is_absolutely_positioned()) {
             auto& cb_state = m_state.get(*box.containing_block());