diff --git a/third_party/blink/renderer/core/css/css_font_face_src_value.cc b/third_party/blink/renderer/core/css/css_font_face_src_value.cc
index a5fd1688e6ee3..d718e81d2e7ef 100644
--- a/third_party/blink/renderer/core/css/css_font_face_src_value.cc
+++ b/third_party/blink/renderer/core/css/css_font_face_src_value.cc
@@ -147,7 +147,13 @@ FontResource& CSSFontFaceSrcValue::Fetch(ExecutionContext* context,
     const CSSUrlData& url_data = src_value_->UrlData();
     const CSSUrlRequestModifiers& modifiers = url_data.GetModifiers();
     const Referrer& referrer = url_data.GetReferrer();
-    ResourceRequest resource_request(url_data.ResolvedUrl());
+    KURL request_url(url_data.ResolvedUrl());
+    if (url_data.PotentiallyDanglingMarkup()) {
+      // The flag is lost when the canonicalized string is re-parsed; restore
+      // it so BaseFetchContext::CanRequestInternal blocks the load.
+      request_url.SetPotentiallyDanglingMarkup();
+    }
+    ResourceRequest resource_request(std::move(request_url));
 
     if (modifiers.referrer_policy) {
       resource_request.SetReferrerPolicy(*modifiers.referrer_policy);
diff --git a/third_party/blink/renderer/core/css/css_uri_value.cc b/third_party/blink/renderer/core/css/css_uri_value.cc
index 829258fa89e30..b4aa6382e9611 100644
--- a/third_party/blink/renderer/core/css/css_uri_value.cc
+++ b/third_party/blink/renderer/core/css/css_uri_value.cc
@@ -60,7 +60,13 @@ const AtomicString& CSSURIValue::NormalizedFragmentIdentifier() const {
 }
 
 KURL CSSURIValue::AbsoluteUrl() const {
-  return KURL(UrlData().ResolvedUrl());
+  KURL url(UrlData().ResolvedUrl());
+  if (UrlData().PotentiallyDanglingMarkup()) {
+    // The flag is lost when the canonicalized string is re-parsed; restore it
+    // so BaseFetchContext::CanRequestInternal blocks the load.
+    url.SetPotentiallyDanglingMarkup();
+  }
+  return url;
 }
 
 bool CSSURIValue::IsLocal(const Document& document) const {
diff --git a/third_party/blink/renderer/core/css/css_url_data.h b/third_party/blink/renderer/core/css/css_url_data.h
index c11d1399754e1..eea59807e202a 100644
--- a/third_party/blink/renderer/core/css/css_url_data.h
+++ b/third_party/blink/renderer/core/css/css_url_data.h
@@ -114,6 +114,9 @@ class CORE_EXPORT CSSUrlData : public GarbageCollected<CSSUrlData> {
     return is_from_origin_clean_style_sheet_;
   }
   bool IsAdRelated() const { return is_ad_related_; }
+  bool PotentiallyDanglingMarkup() const {
+    return potentially_dangling_markup_;
+  }
   const CSSUrlRequestModifiers& GetModifiers() const { return modifiers_; }
 
   // Returns true if this URL is "local" to the specified Document (either by