diff --git a/dom/midi/MIDIMessageEvent.cpp b/dom/midi/MIDIMessageEvent.cpp
index bf7de42bdea5..f3209a2d0d7e 100644
--- a/dom/midi/MIDIMessageEvent.cpp
+++ b/dom/midi/MIDIMessageEvent.cpp
@@ -99,7 +99,6 @@ void MIDIMessageEvent::GetData(JSContext* cx,
       return;
     }
     mRawData.Clear();
-    JS::ExposeObjectToActiveJS(mData);
   }
   aData.set(mData);
 }
diff --git a/dom/promise/Promise.cpp b/dom/promise/Promise.cpp
index 24566f6cf78e..cf9cd435362d 100644
--- a/dom/promise/Promise.cpp
+++ b/dom/promise/Promise.cpp
@@ -359,7 +359,7 @@ static JSObject* CreateNativeHandlerFunction(JSContext* aCx,
 
   JS::Rooted<JSObject*> obj(aCx, JS_GetFunctionObject(func));
 
-  JS::ExposeObjectToActiveJS(aHolder);
+  JS::AssertObjectIsNotGray(aHolder);
   js::SetFunctionNativeReserved(obj, SLOT_NATIVEHANDLER,
                                 JS::ObjectValue(*aHolder));
   js::SetFunctionNativeReserved(obj, SLOT_NATIVEHANDLER_TASK,
diff --git a/dom/prototype/PrototypeDocumentContentSink.cpp b/dom/prototype/PrototypeDocumentContentSink.cpp
index de2a681aecb3..2c5741f604c1 100644
--- a/dom/prototype/PrototypeDocumentContentSink.cpp
+++ b/dom/prototype/PrototypeDocumentContentSink.cpp
@@ -987,9 +987,6 @@ nsresult PrototypeDocumentContentSink::ExecuteScript(
   JS::Rooted<JSObject*> global(cx, JS::CurrentGlobalOrNull(cx));
   NS_ENSURE_TRUE(xpc::Scriptability::Get(global).Allowed(), NS_OK);
 
-  JS::ExposeObjectToActiveJS(global);
-  JSAutoRealm ar(cx, global);
-
   // The script is in the compilation scope. Clone it into the target scope
   // and execute it. On failure, ~AutoScriptEntry will handle exceptions, so
   // there is no need to manually check the return value.
diff --git a/dom/script/ScriptSettings.h b/dom/script/ScriptSettings.h
index 2ff5a6f4f82f..8bc2dc18b355 100644
--- a/dom/script/ScriptSettings.h
+++ b/dom/script/ScriptSettings.h
@@ -214,6 +214,9 @@ class MOZ_STACK_CLASS AutoJSAPI : protected ScriptSettingsStackEntry {
   // If aGlobalObject represents a web-visible global, errors reported by this
   // AutoJSAPI as it comes off the stack will fire the relevant error events and
   // show up in the corresponding web console.
+  //
+  // Successfully initializing the AutoJSAPI will ensure that it enters the
+  // Realm of aGlobalObject's JSObject and exposes that JSObject to active JS.
   MOZ_MUST_USE bool Init(nsIGlobalObject* aGlobalObject);
 
   // This is a helper that grabs the native global associated with aObject and
@@ -231,7 +234,7 @@ class MOZ_STACK_CLASS AutoJSAPI : protected ScriptSettingsStackEntry {
   // show up in the corresponding web console.
   MOZ_MUST_USE bool Init(nsIGlobalObject* aGlobalObject, JSContext* aCx);
 
-  // Convenience functions to take an nsPIDOMWindow* or nsGlobalWindow*,
+  // Convenience functions to take an nsPIDOMWindowInner or nsGlobalWindowInner,
   // when it is more easily available than an nsIGlobalObject.
   MOZ_MUST_USE bool Init(nsPIDOMWindowInner* aWindow);
   MOZ_MUST_USE bool Init(nsPIDOMWindowInner* aWindow, JSContext* aCx);
@@ -310,15 +313,21 @@ class MOZ_STACK_CLASS AutoJSAPI : protected ScriptSettingsStackEntry {
  * |aReason| should be a statically-allocated C string naming the reason we're
  * invoking JavaScript code: "setTimeout", "event", and so on. The devtools use
  * these strings to label JS execution in timeline and profiling displays.
+ *
  */
 class MOZ_STACK_CLASS AutoEntryScript : public AutoJSAPI {
  public:
+  // Constructing the AutoEntryScript will ensure that it enters the
+  // Realm of aGlobalObject's JSObject and exposes that JSObject to active JS.
   AutoEntryScript(nsIGlobalObject* aGlobalObject, const char* aReason,
                   bool aIsMainThread = NS_IsMainThread());
 
   // aObject can be any object from the relevant global. It must not be a
   // cross-compartment wrapper because CCWs are not associated with a single
   // global.
+  //
+  // Constructing the AutoEntryScript will ensure that it enters the
+  // Realm of aObject JSObject and exposes aObject's global to active JS.
   AutoEntryScript(JSObject* aObject, const char* aReason,
                   bool aIsMainThread = NS_IsMainThread());
 
diff --git a/dom/vr/VRDisplay.cpp b/dom/vr/VRDisplay.cpp
index 53d73692bbc7..a79616d11cf2 100644
--- a/dom/vr/VRDisplay.cpp
+++ b/dom/vr/VRDisplay.cpp
@@ -730,9 +730,6 @@ void VRFrameData::LazyCreateMatrix(JS::Heap<JSObject*>& aArray,
       return;
     }
   }
-  if (aArray) {
-    JS::ExposeObjectToActiveJS(aArray);
-  }
   aRetval.set(aArray);
 }
 
diff --git a/dom/xul/nsXULElement.cpp b/dom/xul/nsXULElement.cpp
index cf02a8143e5f..420c7ee424c8 100644
--- a/dom/xul/nsXULElement.cpp
+++ b/dom/xul/nsXULElement.cpp
@@ -2136,9 +2136,6 @@ nsresult nsXULPrototypeScript::Compile(
   // source from the files on demand.
   options.setSourceIsLazy(mOutOfLine);
   JS::Rooted<JSObject*> scope(cx, JS::CurrentGlobalOrNull(cx));
-  if (scope) {
-    JS::ExposeObjectToActiveJS(scope);
-  }
 
   if (aOffThreadReceiver && JS::CanCompileOffThread(cx, options, aTextLength)) {
     if (!JS::CompileOffThread(cx, options, srcBuf,