diff --git a/layout/base/AccessibleCaretManager.cpp b/layout/base/AccessibleCaretManager.cpp
index f6b18047ca00..7f81dd3767b9 100644
--- a/layout/base/AccessibleCaretManager.cpp
+++ b/layout/base/AccessibleCaretManager.cpp
@@ -1406,7 +1406,7 @@ void AccessibleCaretManager::DispatchCaretStateChangedEvent(
     return;
   }
 
-  Selection* sel = GetSelection();
+  const Selection* sel = GetSelection();
   if (!sel) {
     return;
   }
diff --git a/layout/base/nsCaret.cpp b/layout/base/nsCaret.cpp
index e6acdf00feb8..2824b2f9bcac 100644
--- a/layout/base/nsCaret.cpp
+++ b/layout/base/nsCaret.cpp
@@ -354,7 +354,7 @@ nsRect nsCaret::GetGeometryForFrame(nsIFrame* aFrame, int32_t aFrameOffset,
   return rect;
 }
 
-nsIFrame* nsCaret::GetFrameAndOffset(Selection* aSelection,
+nsIFrame* nsCaret::GetFrameAndOffset(const Selection* aSelection,
                                      nsINode* aOverrideNode,
                                      int32_t aOverrideOffset,
                                      int32_t* aFrameOffset,
@@ -390,7 +390,7 @@ nsIFrame* nsCaret::GetFrameAndOffset(Selection* aSelection,
 }
 
 /* static */
-nsIFrame* nsCaret::GetGeometry(Selection* aSelection, nsRect* aRect) {
+nsIFrame* nsCaret::GetGeometry(const Selection* aSelection, nsRect* aRect) {
   int32_t frameOffset;
   nsIFrame* frame = GetFrameAndOffset(aSelection, nullptr, 0, &frameOffset);
   if (frame) {
diff --git a/layout/base/nsCaret.h b/layout/base/nsCaret.h
index cfdf5cd980aa..037ad3f06caa 100644
--- a/layout/base/nsCaret.h
+++ b/layout/base/nsCaret.h
@@ -170,7 +170,7 @@ class nsCaret final : public nsISelectionListener {
    * This rect does not include any extra decorations for bidi.
    * @param aRect must be non-null
    */
-  static nsIFrame* GetGeometry(mozilla::dom::Selection* aSelection,
+  static nsIFrame* GetGeometry(const mozilla::dom::Selection* aSelection,
                                nsRect* aRect);
   static nsIFrame* GetCaretFrameForNodeOffset(
       nsFrameSelection* aFrameSelection, nsIContent* aContentNode,
@@ -186,7 +186,7 @@ class nsCaret final : public nsISelectionListener {
   // @param aUnadjustedFrame return the original frame that the selection is
   // targeting, without any adjustment for painting.
   // @return the frame of the focus node.
-  static nsIFrame* GetFrameAndOffset(mozilla::dom::Selection* aSelection,
+  static nsIFrame* GetFrameAndOffset(const mozilla::dom::Selection* aSelection,
                                      nsINode* aOverrideNode,
                                      int32_t aOverrideOffset,
                                      int32_t* aFrameOffset,
diff --git a/layout/base/nsLayoutUtils.cpp b/layout/base/nsLayoutUtils.cpp
index d366860ec095..3bceada48353 100644
--- a/layout/base/nsLayoutUtils.cpp
+++ b/layout/base/nsLayoutUtils.cpp
@@ -8797,7 +8797,7 @@ void nsLayoutUtils::AppendFrameTextContent(nsIFrame* aFrame,
 }
 
 /* static */
-nsRect nsLayoutUtils::GetSelectionBoundingRect(Selection* aSel) {
+nsRect nsLayoutUtils::GetSelectionBoundingRect(const Selection* aSel) {
   nsRect res;
   // Bounding client rect may be empty after calling GetBoundingClientRect
   // when range is collapsed. So we get caret's rect when range is
diff --git a/layout/base/nsLayoutUtils.h b/layout/base/nsLayoutUtils.h
index c075e3ff6f08..087bdc8ce1a3 100644
--- a/layout/base/nsLayoutUtils.h
+++ b/layout/base/nsLayoutUtils.h
@@ -2732,7 +2732,7 @@ class nsLayoutUtils {
    *
    * @param aSel      Selection to check
    */
-  static nsRect GetSelectionBoundingRect(mozilla::dom::Selection* aSel);
+  static nsRect GetSelectionBoundingRect(const mozilla::dom::Selection* aSel);
 
   /**
    * Calculate the bounding rect of |aContent|, relative to the origin