diff --git a/dom/webauthn/WebAuthnManager.cpp b/dom/webauthn/WebAuthnManager.cpp
index a06271faff62..8015819731af 100644
--- a/dom/webauthn/WebAuthnManager.cpp
+++ b/dom/webauthn/WebAuthnManager.cpp
@@ -177,7 +177,7 @@ nsresult RelaxSameOrigin(nsPIDOMWindowInner* aParent,
  **********************************************************************/
 
 void WebAuthnManager::ClearTransaction() {
-  if (mTransaction.isSome()) {
+  if (!mTransaction.isNothing()) {
     StopListeningForVisibilityEvents();
   }
 
@@ -185,10 +185,20 @@ void WebAuthnManager::ClearTransaction() {
   Unfollow();
 }
 
-void WebAuthnManager::CancelParent() {
+void WebAuthnManager::RejectTransaction(const nsresult& aError) {
+  if (!NS_WARN_IF(mTransaction.isNothing())) {
+    mTransaction.ref().mPromise->MaybeReject(aError);
+  }
+
+  ClearTransaction();
+}
+
+void WebAuthnManager::CancelTransaction(const nsresult& aError) {
   if (!NS_WARN_IF(!mChild || mTransaction.isNothing())) {
     mChild->SendRequestCancel(mTransaction.ref().mId);
   }
+
+  RejectTransaction(aError);
 }
 
 void WebAuthnManager::HandleVisibilityChange() {
@@ -234,7 +244,13 @@ already_AddRefed<Promise> WebAuthnManager::MakeCredential(
 
     // Otherwise, the user may well have clicked away, so let's
     // abort the old transaction and take over control from here.
-    CancelTransaction(NS_ERROR_DOM_ABORT_ERR);
+    CancelTransaction(NS_ERROR_ABORT);
+  }
+
+  // Abort the request if aborted flag is already set.
+  if (aSignal.WasPassed() && aSignal.Value().Aborted()) {
+    promise->MaybeReject(NS_ERROR_DOM_ABORT_ERR);
+    return promise.forget();
   }
 
   nsString origin;
@@ -436,30 +452,11 @@ already_AddRefed<Promise> WebAuthnManager::MakeCredential(
     return promise.forget();
   }
 
-  // Abort the request if aborted flag is already set.
-  if (aSignal.WasPassed() && aSignal.Value().Aborted()) {
-    AutoJSAPI jsapi;
-    if (!jsapi.Init(global)) {
-      promise->MaybeReject(NS_ERROR_DOM_ABORT_ERR);
-      return promise.forget();
-    }
-    JSContext* cx = jsapi.cx();
-    JS::Rooted<JS::Value> reason(cx);
-    aSignal.Value().GetReason(cx, &reason);
-    promise->MaybeReject(reason);
-    return promise.forget();
-  }
-
   WebAuthnMakeCredentialInfo info(
       origin, NS_ConvertUTF8toUTF16(rpId), challenge, clientDataJSON,
       adjustedTimeout, excludeList, rpInfo, userInfo, coseAlgos, extensions,
       authSelection, attestation, context->Top()->Id());
 
-  // Set up the transaction state (including event listeners, etc). Fallible
-  // operations should not be performed below this line, as we must not leave
-  // the transaction state partially initialized. Once the transaction state is
-  // initialized the only valid ways to end the transaction are
-  // CancelTransaction, RejectTransaction, and FinishMakeCredential.
 #ifdef XP_WIN
   if (!WinWebAuthnManager::AreWebAuthNApisAvailable()) {
     ListenForVisibilityEvents();
@@ -506,7 +503,13 @@ already_AddRefed<Promise> WebAuthnManager::GetAssertion(
 
     // Otherwise, the user may well have clicked away, so let's
     // abort the old transaction and take over control from here.
-    CancelTransaction(NS_ERROR_DOM_ABORT_ERR);
+    CancelTransaction(NS_ERROR_ABORT);
+  }
+
+  // Abort the request if aborted flag is already set.
+  if (aSignal.WasPassed() && aSignal.Value().Aborted()) {
+    promise->MaybeReject(NS_ERROR_DOM_ABORT_ERR);
+    return promise.forget();
   }
 
   nsString origin;
@@ -653,30 +656,11 @@ already_AddRefed<Promise> WebAuthnManager::GetAssertion(
     return promise.forget();
   }
 
-  // Abort the request if aborted flag is already set.
-  if (aSignal.WasPassed() && aSignal.Value().Aborted()) {
-    AutoJSAPI jsapi;
-    if (!jsapi.Init(global)) {
-      promise->MaybeReject(NS_ERROR_DOM_ABORT_ERR);
-      return promise.forget();
-    }
-    JSContext* cx = jsapi.cx();
-    JS::Rooted<JS::Value> reason(cx);
-    aSignal.Value().GetReason(cx, &reason);
-    promise->MaybeReject(reason);
-    return promise.forget();
-  }
-
   WebAuthnGetAssertionInfo info(origin, NS_ConvertUTF8toUTF16(rpId), challenge,
                                 clientDataJSON, adjustedTimeout, allowList,
                                 extensions, aOptions.mUserVerification,
                                 context->Top()->Id());
 
-  // Set up the transaction state (including event listeners, etc). Fallible
-  // operations should not be performed below this line, as we must not leave
-  // the transaction state partially initialized. Once the transaction state is
-  // initialized the only valid ways to end the transaction are
-  // CancelTransaction, RejectTransaction, and FinishGetAssertion.
 #ifdef XP_WIN
   if (!WinWebAuthnManager::AreWebAuthNApisAvailable()) {
     ListenForVisibilityEvents();
@@ -720,7 +704,7 @@ already_AddRefed<Promise> WebAuthnManager::Store(const Credential& aCredential,
 
     // Otherwise, the user may well have clicked away, so let's
     // abort the old transaction and take over control from here.
-    CancelTransaction(NS_ERROR_DOM_ABORT_ERR);
+    CancelTransaction(NS_ERROR_ABORT);
   }
 
   promise->MaybeReject(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
@@ -838,21 +822,7 @@ void WebAuthnManager::RequestAborted(const uint64_t& aTransactionId,
 }
 
 void WebAuthnManager::RunAbortAlgorithm() {
-  if (NS_WARN_IF(mTransaction.isNothing())) {
-    return;
-  }
-
-  nsCOMPtr<nsIGlobalObject> global = do_QueryInterface(mParent);
-
-  AutoJSAPI jsapi;
-  if (!jsapi.Init(global)) {
-    CancelTransaction(NS_ERROR_DOM_ABORT_ERR);
-    return;
-  }
-  JSContext* cx = jsapi.cx();
-  JS::Rooted<JS::Value> reason(cx);
-  Signal()->GetReason(cx, &reason);
-  CancelTransaction(reason);
+  CancelTransaction(NS_ERROR_DOM_ABORT_ERR);
 }
 
 }  // namespace mozilla::dom
diff --git a/dom/webauthn/WebAuthnManager.h b/dom/webauthn/WebAuthnManager.h
index 05175c8087cf..8271512a69fd 100644
--- a/dom/webauthn/WebAuthnManager.h
+++ b/dom/webauthn/WebAuthnManager.h
@@ -112,33 +112,17 @@ class WebAuthnManager final : public WebAuthnManagerBase, public AbortFollower {
   void RunAbortAlgorithm() override;
 
  protected:
+  // Cancels the current transaction (by sending a Cancel message to the
+  // parent) and rejects it by calling RejectTransaction().
+  void CancelTransaction(const nsresult& aError);
   // Upon a visibility change, makes note of it in the current transaction.
   void HandleVisibilityChange() override;
 
  private:
   virtual ~WebAuthnManager();
 
-  // Send a Cancel message to the parent, reject the promise with the given
-  // reason (an nsresult or JS::Handle<JS::Value>), and clear the transaction.
-  template <typename T>
-  void CancelTransaction(const T& aReason) {
-    CancelParent();
-    RejectTransaction(aReason);
-  }
-
-  // Reject the promise with the given reason (an nsresult or JS::Value), and
-  // clear the transaction.
-  template <typename T>
-  void RejectTransaction(const T& aReason) {
-    if (!NS_WARN_IF(mTransaction.isNothing())) {
-      mTransaction.ref().mPromise->MaybeReject(aReason);
-    }
-
-    ClearTransaction();
-  }
-
-  // Send a Cancel message to the parent.
-  void CancelParent();
+  // Rejects the current transaction and calls ClearTransaction().
+  void RejectTransaction(const nsresult& aError);
 
   // Clears all information we have about the current transaction.
   void ClearTransaction();
diff --git a/testing/web-platform/meta/webauthn/createcredential-abort.https.html.ini b/testing/web-platform/meta/webauthn/createcredential-abort.https.html.ini
new file mode 100644
index 000000000000..ab1b2545154c
--- /dev/null
+++ b/testing/web-platform/meta/webauthn/createcredential-abort.https.html.ini
@@ -0,0 +1,12 @@
+[createcredential-abort.https.html]
+  [navigator.credentials.create() after abort reason]
+    expected: FAIL
+
+  [navigator.credentials.create() before abort reason]
+    expected: FAIL
+
+  [navigator.credentials.create() after abort reason with Error]
+    expected: FAIL
+
+  [navigator.credentials.create() before abort reason with Error]
+    expected: FAIL
diff --git a/testing/web-platform/meta/webauthn/getcredential-abort.https.html.ini b/testing/web-platform/meta/webauthn/getcredential-abort.https.html.ini
new file mode 100644
index 000000000000..1ea6b6c7318b
--- /dev/null
+++ b/testing/web-platform/meta/webauthn/getcredential-abort.https.html.ini
@@ -0,0 +1,12 @@
+[getcredential-abort.https.html]
+  [navigator.credentials.get() after abort reason]
+    expected: FAIL
+
+  [navigator.credentials.get() before abort reason]
+    expected: FAIL
+
+  [navigator.credentials.get() after abort reason with Error]
+    expected: FAIL
+
+  [navigator.credentials.get() before abort reason with Error]
+    expected: FAIL