--- a/accessible/mac/GeckoTextMarker.h
+++ b/accessible/mac/GeckoTextMarker.h
@@ -51,16 +51,18 @@ class GeckoTextMarker final {
 
   bool operator<(const GeckoTextMarker& aPoint) const;
 
   AccessibleOrProxy mContainer;
   int32_t mOffset;
 
  private:
   uint32_t CharacterCount(const AccessibleOrProxy& aContainer);
+
+  bool IsEditableRoot();
 };
 
 class GeckoTextMarkerRange final {
  public:
   GeckoTextMarkerRange(const GeckoTextMarker& aStart, const GeckoTextMarker& aEnd)
       : mStart(aStart), mEnd(aEnd) {}
 
   GeckoTextMarkerRange(AccessibleOrProxy aDoc, AXTextMarkerRangeRef aTextMarkerRange);

--- a/accessible/mac/GeckoTextMarker.mm
+++ b/accessible/mac/GeckoTextMarker.mm
@@ -95,31 +95,51 @@ bool GeckoTextMarker::operator<(const Ge
       return child1.IndexInParent() < child2.IndexInParent();
     }
   }
 
   MOZ_ASSERT_UNREACHABLE("Broken tree?!");
   return false;
 }
 
+bool GeckoTextMarker::IsEditableRoot() {
+  uint64_t state =
+      mContainer.IsProxy() ? mContainer.AsProxy()->State() : mContainer.AsAccessible()->State();
+  if ((state & states::EDITABLE) == 0) {
+    return false;
+  }
+
+  AccessibleOrProxy parent = mContainer.Parent();
+  if (parent.IsNull()) {
+    // Not sure when this can happen, but it would technically be an editable root.
+    return true;
+  }
+
+  state = parent.IsProxy() ? parent.AsProxy()->State() : parent.AsAccessible()->State();
+
+  return (state & states::EDITABLE) == 0;
+}
+
 void GeckoTextMarker::NormalizeNext() {
   if (AtEnd()) {
     // If this is the end of the current container, mutate to its parent's
     // end offset.
     bool unused;
     uint32_t endOffset = mContainer.IsProxy() ? mContainer.AsProxy()->EndOffset(&unused)
                                               : mContainer.AsAccessible()->EndOffset();
 
     if (endOffset != 0) {
-      mContainer = mContainer.Parent();
-      mOffset = endOffset;
+      if (!IsEditableRoot()) {
+        mContainer = mContainer.Parent();
+        mOffset = endOffset;
 
-      // Call NormalizeNext recursively to get top-most link if at the end of one,
-      // or innermost link if at the beginning.
-      NormalizeNext();
+        // Call NormalizeNext recursively to get top-most link if at the end of one,
+        // or innermost link if at the beginning.
+        NormalizeNext();
+      }
     }
   } else {
     AccessibleOrProxy link;
 
     if (mContainer.IsProxy()) {
       ProxyAccessible* proxy = mContainer.AsProxy();
       link = proxy->LinkAt(proxy->LinkIndexAtOffset(mOffset));
     } else if (HyperTextAccessible* ht = mContainer.AsAccessible()->AsHyperText()) {
@@ -141,22 +161,24 @@ void GeckoTextMarker::NormalizeNext() {
 void GeckoTextMarker::NormalizePrevious() {
   if (mOffset == 0) {
     // If we are at the beginning of a container, mutate to its parent's start offset.
     bool unused;
     uint32_t startOffset = mContainer.IsProxy() ? mContainer.AsProxy()->StartOffset(&unused)
                                                 : mContainer.AsAccessible()->StartOffset();
 
     if (startOffset != 0) {
-      mContainer = mContainer.Parent();
-      mOffset = startOffset;
+      if (!IsEditableRoot()) {
+        mContainer = mContainer.Parent();
+        mOffset = startOffset;
 
-      // Call NormalizePrevious recursively to get top-most link if at the start of one,
-      // or innermost link if at the end.
-      NormalizePrevious();
+        // Call NormalizePrevious recursively to get top-most link if at the start of one,
+        // or innermost link if at the end.
+        NormalizePrevious();
+      }
     }
   } else {
     AccessibleOrProxy link;
 
     if (mContainer.IsProxy()) {
       ProxyAccessible* proxy = mContainer.AsProxy();
       link = proxy->LinkAt(proxy->LinkIndexAtOffset(mOffset - 1));
     } else if (HyperTextAccessible* ht = mContainer.AsAccessible()->AsHyperText()) {