diff --git a/editor/libeditor/HTMLEditUtils.h b/editor/libeditor/HTMLEditUtils.h
index d10a481d5851..46e1c1c91bbb 100644
--- a/editor/libeditor/HTMLEditUtils.h
+++ b/editor/libeditor/HTMLEditUtils.h
@@ -568,12 +568,25 @@ class HTMLEditUtils final {
     // If there is a non-editable element if and only if scanning from editable
     // node, return it too.
     LeafNodeOrNonEditableNode,
+    // Ignore non-editable content at walking the tree.
+    OnlyEditableLeafNode,
   };
   using LeafNodeTypes = EnumSet<LeafNodeType>;
-  static nsIContent* GetLastLeafContent(nsINode& aNode,
-                                        const LeafNodeTypes& aLeafNodeTypes) {
-    for (nsIContent* content = aNode.GetLastChild(); content;
-         content = content->GetLastChild()) {
+  static nsIContent* GetLastLeafContent(
+      nsINode& aNode, const LeafNodeTypes& aLeafNodeTypes,
+      const Element* aAncestorLimiter = nullptr) {
+    MOZ_ASSERT_IF(
+        aLeafNodeTypes.contains(LeafNodeType::OnlyEditableLeafNode),
+        !aLeafNodeTypes.contains(LeafNodeType::LeafNodeOrNonEditableNode));
+    for (nsIContent* content = aNode.GetLastChild(); content;) {
+      if (aLeafNodeTypes.contains(LeafNodeType::OnlyEditableLeafNode) &&
+          !EditorUtils::IsEditableContent(*content,
+                                          EditorUtils::EditorType::HTML)) {
+        content = HTMLEditUtils::GetPreviousContent(
+            *content, {WalkTreeOption::IgnoreNonEditableNode},
+            aAncestorLimiter);
+        continue;
+      }
       if (aLeafNodeTypes.contains(LeafNodeType::LeafNodeOrChildBlock) &&
           HTMLEditUtils::IsBlockElement(*content)) {
         return content;
@@ -585,6 +598,7 @@ class HTMLEditUtils final {
           aNode.IsEditable() && !content->IsEditable()) {
         return content;
       }
+      content = content->GetLastChild();
     }
     return nullptr;
   }
@@ -594,10 +608,21 @@ class HTMLEditUtils final {
    * on aLeafNodeTypes whether this scans into a block child or treat block as a
    * leaf.
    */
-  static nsIContent* GetFirstLeafContent(const nsINode& aNode,
-                                         const LeafNodeTypes& aLeafNodeTypes) {
-    for (nsIContent* content = aNode.GetFirstChild(); content;
-         content = content->GetFirstChild()) {
+  static nsIContent* GetFirstLeafContent(
+      const nsINode& aNode, const LeafNodeTypes& aLeafNodeTypes,
+      const Element* aAncestorLimiter = nullptr) {
+    MOZ_ASSERT_IF(
+        aLeafNodeTypes.contains(LeafNodeType::OnlyEditableLeafNode),
+        !aLeafNodeTypes.contains(LeafNodeType::LeafNodeOrNonEditableNode));
+    for (nsIContent* content = aNode.GetFirstChild(); content;) {
+      if (aLeafNodeTypes.contains(LeafNodeType::OnlyEditableLeafNode) &&
+          !EditorUtils::IsEditableContent(*content,
+                                          EditorUtils::EditorType::HTML)) {
+        content = HTMLEditUtils::GetNextContent(
+            *content, {WalkTreeOption::IgnoreNonEditableNode},
+            aAncestorLimiter);
+        continue;
+      }
       if (aLeafNodeTypes.contains(LeafNodeType::LeafNodeOrChildBlock) &&
           HTMLEditUtils::IsBlockElement(*content)) {
         return content;
@@ -609,6 +634,7 @@ class HTMLEditUtils final {
           aNode.IsEditable() && !content->IsEditable()) {
         return content;
       }
+      content = content->GetFirstChild();
     }
     return nullptr;
   }
@@ -632,6 +658,10 @@ class HTMLEditUtils final {
       const nsIContent& aStartContent, const nsIContent& aCurrentBlock,
       const LeafNodeTypes& aLeafNodeTypes,
       const Element* aAncestorLimiter = nullptr) {
+    MOZ_ASSERT_IF(
+        aLeafNodeTypes.contains(LeafNodeType::OnlyEditableLeafNode),
+        !aLeafNodeTypes.contains(LeafNodeType::LeafNodeOrNonEditableNode));
+
     if (&aStartContent == aAncestorLimiter) {
       return nullptr;
     }
@@ -691,6 +721,11 @@ class HTMLEditUtils final {
       const nsIContent& aCurrentBlock, const LeafNodeTypes& aLeafNodeTypes,
       const Element* aAncestorLimiter = nullptr) {
     MOZ_ASSERT(aStartPoint.IsSet());
+    MOZ_ASSERT_IF(
+        aLeafNodeTypes.contains(LeafNodeType::OnlyEditableLeafNode),
+        !aLeafNodeTypes.contains(LeafNodeType::LeafNodeOrNonEditableNode));
+    NS_ASSERTION(!aLeafNodeTypes.contains(LeafNodeType::OnlyEditableLeafNode),
+                 "Not implemented yet");
 
     if (!aStartPoint.IsInContentNode()) {
       return nullptr;
@@ -759,6 +794,12 @@ class HTMLEditUtils final {
       const nsIContent& aStartContent, const nsIContent& aCurrentBlock,
       const LeafNodeTypes& aLeafNodeTypes,
       const Element* aAncestorLimiter = nullptr) {
+    MOZ_ASSERT_IF(
+        aLeafNodeTypes.contains(LeafNodeType::OnlyEditableLeafNode),
+        !aLeafNodeTypes.contains(LeafNodeType::LeafNodeOrNonEditableNode));
+    NS_ASSERTION(!aLeafNodeTypes.contains(LeafNodeType::OnlyEditableLeafNode),
+                 "Not implemented yet");
+
     if (&aStartContent == aAncestorLimiter) {
       return nullptr;
     }
@@ -818,6 +859,11 @@ class HTMLEditUtils final {
       const nsIContent& aCurrentBlock, const LeafNodeTypes& aLeafNodeTypes,
       const Element* aAncestorLimiter = nullptr) {
     MOZ_ASSERT(aStartPoint.IsSet());
+    MOZ_ASSERT_IF(
+        aLeafNodeTypes.contains(LeafNodeType::OnlyEditableLeafNode),
+        !aLeafNodeTypes.contains(LeafNodeType::LeafNodeOrNonEditableNode));
+    NS_ASSERTION(!aLeafNodeTypes.contains(LeafNodeType::OnlyEditableLeafNode),
+                 "Not implemented yet");
 
     if (!aStartPoint.IsInContentNode()) {
       return nullptr;
diff --git a/editor/libeditor/HTMLEditor.cpp b/editor/libeditor/HTMLEditor.cpp
index c7a6c8c244e6..9245065ab9ff 100644
--- a/editor/libeditor/HTMLEditor.cpp
+++ b/editor/libeditor/HTMLEditor.cpp
@@ -4932,42 +4932,6 @@ nsresult HTMLEditor::DeleteSelectionAndPrepareToCreateNode() {
   return error.StealNSResult();
 }
 
-nsIContent* HTMLEditor::GetFirstEditableLeaf(nsINode& aNode) const {
-  Element* editingHost = GetActiveEditingHost();
-  if (NS_WARN_IF(!editingHost) ||
-      editingHost->IsInclusiveDescendantOf(&aNode)) {
-    return nullptr;
-  }
-  nsIContent* child =
-      HTMLEditUtils::GetFirstLeafContent(aNode, {LeafNodeType::OnlyLeafNode});
-  while (child && (!EditorUtils::IsEditableContent(*child, EditorType::HTML) ||
-                   child->HasChildren())) {
-    child = HTMLEditUtils::GetNextContent(
-        *child, {WalkTreeOption::IgnoreNonEditableNode},
-        aNode.IsElement() ? aNode.AsElement() : editingHost);
-  }
-
-  return child;
-}
-
-nsIContent* HTMLEditor::GetLastEditableLeaf(nsINode& aNode) const {
-  Element* editingHost = GetActiveEditingHost();
-  if (NS_WARN_IF(!editingHost) ||
-      editingHost->IsInclusiveDescendantOf(&aNode)) {
-    return nullptr;
-  }
-  nsIContent* child =
-      HTMLEditUtils::GetLastLeafContent(aNode, {LeafNodeType::OnlyLeafNode});
-  while (child && (!EditorUtils::IsEditableContent(*child, EditorType::HTML) ||
-                   child->HasChildren())) {
-    child = HTMLEditUtils::GetPreviousContent(
-        *child, {WalkTreeOption::IgnoreNonEditableNode},
-        aNode.IsElement() ? aNode.AsElement() : editingHost);
-  }
-
-  return child;
-}
-
 bool HTMLEditor::IsEmpty() const {
   if (mPaddingBRElementForEmptyEditor) {
     return true;
diff --git a/editor/libeditor/HTMLEditor.h b/editor/libeditor/HTMLEditor.h
index c80d9d5cde8b..e383a81cc78f 100644
--- a/editor/libeditor/HTMLEditor.h
+++ b/editor/libeditor/HTMLEditor.h
@@ -917,9 +917,6 @@ class HTMLEditor final : public TextEditor,
   SplitAncestorStyledInlineElementsAt(const EditorDOMPoint& aPointToSplit,
                                       nsAtom* aProperty, nsAtom* aAttribute);
 
-  nsIContent* GetFirstEditableLeaf(nsINode& aNode) const;
-  nsIContent* GetLastEditableLeaf(nsINode& aNode) const;
-
   [[nodiscard]] MOZ_CAN_RUN_SCRIPT nsresult GetInlinePropertyBase(
       nsAtom& aHTMLProperty, nsAtom* aAttribute, const nsAString* aValue,
       bool* aFirst, bool* aAny, bool* aAll, nsAString* outValue) const;
diff --git a/editor/libeditor/HTMLEditorDataTransfer.cpp b/editor/libeditor/HTMLEditorDataTransfer.cpp
index a79c62ce998e..1dc922c9381f 100644
--- a/editor/libeditor/HTMLEditorDataTransfer.cpp
+++ b/editor/libeditor/HTMLEditorDataTransfer.cpp
@@ -82,6 +82,7 @@ class nsISupports;
 namespace mozilla {
 
 using namespace dom;
+using LeafNodeType = HTMLEditUtils::LeafNodeType;
 
 #define kInsertCookie "_moz_Insert Here_moz_"
 
@@ -353,8 +354,9 @@ HTMLEditor::HTMLWithContextInserter::GetNewCaretPointAfterInsertingHTML(
   // but don't cross tables
   nsIContent* containerContent = nullptr;
   if (!HTMLEditUtils::IsTable(aLastInsertedPoint.GetChild())) {
-    containerContent =
-        mHTMLEditor.GetLastEditableLeaf(*aLastInsertedPoint.GetChild());
+    containerContent = HTMLEditUtils::GetLastLeafContent(
+        *aLastInsertedPoint.GetChild(), {LeafNodeType::OnlyEditableLeafNode},
+        aLastInsertedPoint.GetChild()->GetAsElementOrParentElement());
     if (containerContent) {
       Element* mostDistantInclusiveAncestorTableElement = nullptr;
       for (Element* maybeTableElement =
diff --git a/editor/libeditor/HTMLEditorDeleteHandler.cpp b/editor/libeditor/HTMLEditorDeleteHandler.cpp
index 5f9cb6809be8..80131656fdb2 100644
--- a/editor/libeditor/HTMLEditorDeleteHandler.cpp
+++ b/editor/libeditor/HTMLEditorDeleteHandler.cpp
@@ -48,6 +48,7 @@ namespace mozilla {
 using namespace dom;
 using EmptyCheckOption = HTMLEditUtils::EmptyCheckOption;
 using InvisibleWhiteSpaces = HTMLEditUtils::InvisibleWhiteSpaces;
+using LeafNodeType = HTMLEditUtils::LeafNodeType;
 using StyleDifference = HTMLEditUtils::StyleDifference;
 using TableBoundary = HTMLEditUtils::TableBoundary;
 using WalkTreeOption = HTMLEditUtils::WalkTreeOption;
@@ -2434,13 +2435,15 @@ bool HTMLEditor::AutoDeleteRangesHandler::AutoBlockElementsJoiner::
 
   // First find the adjacent node in the block
   if (aDirectionAndAmount == nsIEditor::ePrevious) {
-    mLeafContentInOtherBlock =
-        aHTMLEditor.GetLastEditableLeaf(aOtherBlockElement);
+    mLeafContentInOtherBlock = HTMLEditUtils::GetLastLeafContent(
+        aOtherBlockElement, {LeafNodeType::OnlyEditableLeafNode},
+        &aOtherBlockElement);
     mLeftContent = mLeafContentInOtherBlock;
     mRightContent = aCaretPoint.GetContainerAsContent();
   } else {
-    mLeafContentInOtherBlock =
-        aHTMLEditor.GetFirstEditableLeaf(aOtherBlockElement);
+    mLeafContentInOtherBlock = HTMLEditUtils::GetFirstLeafContent(
+        aOtherBlockElement, {LeafNodeType::OnlyEditableLeafNode},
+        &aOtherBlockElement);
     mLeftContent = aCaretPoint.GetContainerAsContent();
     mRightContent = mLeafContentInOtherBlock;
   }