--- a/dom/base/nsDocument.cpp
+++ b/dom/base/nsDocument.cpp
@@ -12310,16 +12310,75 @@ public:
   NS_IMETHOD Run() final;
 
 private:
   nsWeakPtr mElement;
   nsWeakPtr mDocument;
   bool mUserInputOrChromeCaller;
 };
 
+static bool
+ShouldLockPointer(Element* aElement, Element* aCurrentLock,
+                  bool aNoFocusCheck = false)
+{
+  // Check if pointer lock pref is enabled
+  if (!Preferences::GetBool("full-screen-api.pointer-lock.enabled")) {
+    NS_WARNING("ShouldLockPointer(): Pointer Lock pref not enabled");
+    return false;
+  }
+
+  nsCOMPtr<nsIDocument> ownerDoc = aElement->OwnerDoc();
+  if (aCurrentLock && aCurrentLock->OwnerDoc() != ownerDoc) {
+    NS_WARNING("ShouldLockPointer(): Existing pointer lock element in a different document");
+    return false;
+  }
+
+  if (!aElement->IsInUncomposedDoc()) {
+    NS_WARNING("ShouldLockPointer(): Element without Document");
+    return false;
+  }
+
+  if (ownerDoc->GetSandboxFlags() & SANDBOXED_POINTER_LOCK) {
+    NS_WARNING("ShouldLockPointer(): Document is sandboxed and doesn't allow pointer-lock");
+    return false;
+  }
+
+  // Check if the element is in a document with a docshell.
+  if (!ownerDoc->GetContainer()) {
+    return false;
+  }
+  nsCOMPtr<nsPIDOMWindowOuter> ownerWindow = ownerDoc->GetWindow();
+  if (!ownerWindow) {
+    return false;
+  }
+  nsCOMPtr<nsPIDOMWindowInner> ownerInnerWindow = ownerDoc->GetInnerWindow();
+  if (!ownerInnerWindow) {
+    return false;
+  }
+  if (ownerWindow->GetCurrentInnerWindow() != ownerInnerWindow) {
+    return false;
+  }
+
+  nsCOMPtr<nsPIDOMWindowOuter> top = ownerWindow->GetScriptableTop();
+  if (!top || !top->GetExtantDoc() || top->GetExtantDoc()->Hidden()) {
+    NS_WARNING("ShouldLockPointer(): Top document isn't visible.");
+    return false;
+  }
+
+  if (!aNoFocusCheck) {
+    mozilla::ErrorResult rv;
+    if (!top->GetExtantDoc()->HasFocus(rv)) {
+      NS_WARNING("ShouldLockPointer(): Top document isn't focused.");
+      return false;
+    }
+  }
+
+  return true;
+}
+
 NS_IMETHODIMP
 PointerLockRequest::Run()
 {
   nsCOMPtr<Element> e = do_QueryReferent(mElement);
   nsCOMPtr<nsIDocument> doc = do_QueryReferent(mDocument);
   nsDocument* d = static_cast<nsDocument*>(doc.get());
   if (!e || !d || e->GetUncomposedDoc() != d) {
     DispatchPointerLockError(d);
@@ -12329,17 +12388,17 @@ PointerLockRequest::Run()
   nsCOMPtr<Element> pointerLockedElement =
     do_QueryReferent(EventStateManager::sPointerLockedElement);
   if (e == pointerLockedElement) {
     DispatchPointerLockChange(d);
     return NS_OK;
   }
 
   // Note, we must bypass focus change, so pass true as the last parameter!
-  if (!d->ShouldLockPointer(e, pointerLockedElement, true)) {
+  if (!ShouldLockPointer(e, pointerLockedElement, true)) {
     DispatchPointerLockError(d);
     return NS_OK;
   }
 
   // If it is neither user input initiated, nor requested in fullscreen,
   // it should be rejected.
   if (!mUserInputOrChromeCaller && !doc->GetFullscreenElement()) {
     DispatchPointerLockError(d);
@@ -12386,75 +12445,16 @@ nsDocument::RequestPointerLock(Element* 
 
   bool userInputOrChromeCaller = EventStateManager::IsHandlingUserInput() ||
                                  nsContentUtils::IsCallerChrome();
   NS_DispatchToMainThread(new PointerLockRequest(aElement,
                                                  userInputOrChromeCaller));
 }
 
 bool
-nsDocument::ShouldLockPointer(Element* aElement, Element* aCurrentLock,
-                              bool aNoFocusCheck)
-{
-  // Check if pointer lock pref is enabled
-  if (!Preferences::GetBool("full-screen-api.pointer-lock.enabled")) {
-    NS_WARNING("ShouldLockPointer(): Pointer Lock pref not enabled");
-    return false;
-  }
-
-  if (aCurrentLock && aCurrentLock->OwnerDoc() != aElement->OwnerDoc()) {
-    NS_WARNING("ShouldLockPointer(): Existing pointer lock element in a different document");
-    return false;
-  }
-
-  if (!aElement->IsInUncomposedDoc()) {
-    NS_WARNING("ShouldLockPointer(): Element without Document");
-    return false;
-  }
-
-  if (mSandboxFlags & SANDBOXED_POINTER_LOCK) {
-    NS_WARNING("ShouldLockPointer(): Document is sandboxed and doesn't allow pointer-lock");
-    return false;
-  }
-
-  // Check if the element is in a document with a docshell.
-  nsCOMPtr<nsIDocument> ownerDoc = aElement->OwnerDoc();
-  if (!ownerDoc->GetContainer()) {
-    return false;
-  }
-  nsCOMPtr<nsPIDOMWindowOuter> ownerWindow = ownerDoc->GetWindow();
-  if (!ownerWindow) {
-    return false;
-  }
-  nsCOMPtr<nsPIDOMWindowInner> ownerInnerWindow = ownerDoc->GetInnerWindow();
-  if (!ownerInnerWindow) {
-    return false;
-  }
-  if (ownerWindow->GetCurrentInnerWindow() != ownerInnerWindow) {
-    return false;
-  }
-
-  nsCOMPtr<nsPIDOMWindowOuter> top = ownerWindow->GetScriptableTop();
-  if (!top || !top->GetExtantDoc() || top->GetExtantDoc()->Hidden()) {
-    NS_WARNING("ShouldLockPointer(): Top document isn't visible.");
-    return false;
-  }
-
-  if (!aNoFocusCheck) {
-    mozilla::ErrorResult rv;
-    if (!top->GetExtantDoc()->HasFocus(rv)) {
-      NS_WARNING("ShouldLockPointer(): Top document isn't focused.");
-      return false;
-    }
-  }
-
-  return true;
-}
-
-bool
 nsDocument::SetPointerLock(Element* aElement, int aCursorStyle)
 {
   MOZ_ASSERT(!aElement || aElement->OwnerDoc() == this,
              "We should be either unlocking pointer (aElement is nullptr), "
              "or locking pointer to an element in this document");
 #ifdef DEBUG
   if (!aElement) {
     nsCOMPtr<nsIDocument> pointerLockedDoc =

--- a/dom/base/nsDocument.h
+++ b/dom/base/nsDocument.h
@@ -1263,18 +1263,16 @@ public:
   // Returns the top element from the full-screen stack.
   Element* FullScreenStackTop();
 
   // DOM-exposed fullscreen API
   bool FullscreenEnabled() override;
   Element* GetFullscreenElement() override;
 
   void RequestPointerLock(Element* aElement) override;
-  bool ShouldLockPointer(Element* aElement, Element* aCurrentLock,
-                         bool aNoFocusCheck = false);
   bool SetPointerLock(Element* aElement, int aCursorStyle);
   static void UnlockPointer(nsIDocument* aDoc = nullptr);
 
   void SetCurrentOrientation(mozilla::dom::OrientationType aType,
                              uint16_t aAngle) override;
   uint16_t CurrentOrientationAngle() const override;
   mozilla::dom::OrientationType CurrentOrientationType() const override;
   void SetOrientationPendingPromise(mozilla::dom::Promise* aPromise) override;