--- a/layout/base/nsCSSFrameConstructor.cpp
+++ b/layout/base/nsCSSFrameConstructor.cpp
@@ -3556,26 +3556,17 @@ nsCSSFrameConstructor::FindHTMLData(Elem
     // <legend> is only special inside fieldset, we only check the frame tree
     // parent because the content tree parent may not be a <fieldset> due to
     // display:contents, Shadow DOM, or XBL. For floated or absolutely
     // positioned legends we want to construct by display type and
     // not do special legend stuff.
     return nullptr;
   }
 
-  if (aTag == nsGkAtoms::details || aTag == nsGkAtoms::summary) {
-    if (!HTMLDetailsElement::IsDetailsEnabled()) {
-      return nullptr;
-    }
-  }
-
-  if (aTag == nsGkAtoms::summary &&
-      (!aParentFrame || aParentFrame->GetType() != nsGkAtoms::detailsFrame)) {
-    // <summary> is special only if it is a direct child of <details>. If it
-    // isn't, construct it as a normal block frame instead of a summary frame.
+  if (aTag == nsGkAtoms::details && !HTMLDetailsElement::IsDetailsEnabled()) {
     return nullptr;
   }
 
   static const FrameConstructionDataByTag sHTMLData[] = {
     SIMPLE_TAG_CHAIN(img, nsCSSFrameConstructor::FindImgData),
     SIMPLE_TAG_CHAIN(mozgeneratedcontentimage,
                      nsCSSFrameConstructor::FindImgData),
     { &nsGkAtoms::br,