1 files changed, 15 insertions, 1 deletions
diff --git a/chromium/third_party/blink/renderer/core/layout/multi_column_fragmentainer_group.cc b/chromium/third_party/blink/renderer/core/layout/multi_column_fragmentainer_group.cc
index aee79c33aeb..f808c669e5c 100644
--- a/chromium/third_party/blink/renderer/core/layout/multi_column_fragmentainer_group.cc
+++ b/chromium/third_party/blink/renderer/core/layout/multi_column_fragmentainer_group.cc
@@ -329,11 +329,25 @@ unsigned MultiColumnFragmentainerGroup::ActualColumnCount() const {
 
 void MultiColumnFragmentainerGroup::SetColumnBlockSizeFromNG(
     LayoutUnit block_size) {
-  DCHECK(!is_logical_height_known_ || logical_height_ == block_size);
+  // We clamp the fragmentainer block size from 0 to 1 for legacy write-back
+  // if there is content that overflows the zero-height fragmentainer. However,
+  // if the last fragmentainer contains no overflow, while previous
+  // fragmentainers do, the known height may be different than the |block_size|
+  // passed in. Don't override the stored height if this is the case.
+  DCHECK(!is_logical_height_known_ || logical_height_ == block_size ||
+         block_size == LayoutUnit());
+  if (is_logical_height_known_)
+    return;
   logical_height_ = block_size;
   is_logical_height_known_ = true;
 }
 
+void MultiColumnFragmentainerGroup::ExtendColumnBlockSizeFromNG(
+    LayoutUnit block_size) {
+  DCHECK(is_logical_height_known_);
+  logical_height_ += block_size;
+}
+
 LayoutUnit MultiColumnFragmentainerGroup::HeightAdjustedForRowOffset(
     LayoutUnit height) const {
   LayoutUnit adjusted_height =