diff --git a/Source/WebCore/ChangeLog b/Source/WebCore/ChangeLog
index e5d2029..6c2c66d 100644
--- a/Source/WebCore/ChangeLog
+++ b/Source/WebCore/ChangeLog
@@ -1,3 +1,17 @@
+2021-10-13  Rob Buis  <rbuis@igalia.com>
+
+        Determine viewport distances for lazy image loading
+        https://bugs.webkit.org/show_bug.cgi?id=203557
+
+        Reviewed by Simon Fraser.
+
+        Determine appropriate lazy image loading viewport distances
+        for desktop and mobile devices by using a lazy load distance
+        of one viewport in all directions.
+
+        * html/LazyLoadImageObserver.cpp:
+        (WebCore::LazyLoadImageObserver::intersectionObserver):
+
 2021-10-13  Jean-Yves Avenard  <jya@apple.com>
 
         Compilation error: error: definition of implicit copy assignment operator in AppHighlightRangeData.h
diff --git a/Source/WebCore/html/LazyLoadImageObserver.cpp b/Source/WebCore/html/LazyLoadImageObserver.cpp
index 836dc82..176a6ef 100644
--- a/Source/WebCore/html/LazyLoadImageObserver.cpp
+++ b/Source/WebCore/html/LazyLoadImageObserver.cpp
@@ -29,7 +29,6 @@
 #include "Frame.h"
 #include "HTMLImageElement.h"
 #include "IntersectionObserverCallback.h"
-#include "RenderStyle.h"
 
 #include <limits>
 
@@ -86,7 +85,8 @@
 {
     if (!m_observer) {
         auto callback = LazyImageLoadIntersectionObserverCallback::create(document);
-        IntersectionObserver::Init options { std::nullopt, emptyString(), { } };
+        static NeverDestroyed<const String> lazyLoadingRootMarginFallback(MAKE_STATIC_STRING_IMPL("100%"));
+        IntersectionObserver::Init options { std::nullopt, lazyLoadingRootMarginFallback, { } };
         auto observer = IntersectionObserver::create(document, WTFMove(callback), WTFMove(options));
         if (observer.hasException())
             return nullptr;