diff --git a/dom/credentialmanagement/CredentialsContainer.cpp b/dom/credentialmanagement/CredentialsContainer.cpp
index ab60b9e7ed5d..9fb879770deb 100644
--- a/dom/credentialmanagement/CredentialsContainer.cpp
+++ b/dom/credentialmanagement/CredentialsContainer.cpp
@@ -124,6 +124,14 @@ void CredentialsContainer::EnsureWebAuthnManager() {
   }
 }
 
+already_AddRefed<WebAuthnManager> CredentialsContainer::GetWebAuthnManager() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  EnsureWebAuthnManager();
+  RefPtr<WebAuthnManager> ref = mManager;
+  return ref.forget();
+}
+
 JSObject* CredentialsContainer::WrapObject(JSContext* aCx,
                                            JS::Handle<JSObject*> aGivenProto) {
   return CredentialsContainer_Binding::Wrap(aCx, this, aGivenProto);
diff --git a/dom/credentialmanagement/CredentialsContainer.h b/dom/credentialmanagement/CredentialsContainer.h
index 2347e8458241..1c4c53bd9d01 100644
--- a/dom/credentialmanagement/CredentialsContainer.h
+++ b/dom/credentialmanagement/CredentialsContainer.h
@@ -22,6 +22,8 @@ class CredentialsContainer final : public nsISupports, public nsWrapperCache {
 
   nsPIDOMWindowInner* GetParentObject() const { return mParent; }
 
+  already_AddRefed<WebAuthnManager> GetWebAuthnManager();
+
   virtual JSObject* WrapObject(JSContext* aCx,
                                JS::Handle<JSObject*> aGivenProto) override;
 
diff --git a/dom/webauthn/AndroidWebAuthnService.cpp b/dom/webauthn/AndroidWebAuthnService.cpp
index ad53f298579b..3862275e49ab 100644
--- a/dom/webauthn/AndroidWebAuthnService.cpp
+++ b/dom/webauthn/AndroidWebAuthnService.cpp
@@ -33,6 +33,11 @@ namespace dom {
 
 NS_IMPL_ISUPPORTS(AndroidWebAuthnService, nsIWebAuthnService)
 
+NS_IMETHODIMP
+AndroidWebAuthnService::GetIsUVPAA(bool* aAvailable) {
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
 NS_IMETHODIMP
 AndroidWebAuthnService::MakeCredential(uint64_t aTransactionId,
                                        uint64_t browsingContextId,
diff --git a/dom/webauthn/PWebAuthnTransaction.ipdl b/dom/webauthn/PWebAuthnTransaction.ipdl
index e4b8e90a4ee2..f9d59209dbc1 100644
--- a/dom/webauthn/PWebAuthnTransaction.ipdl
+++ b/dom/webauthn/PWebAuthnTransaction.ipdl
@@ -141,6 +141,7 @@ async protocol PWebAuthnTransaction {
   parent:
     async RequestRegister(uint64_t aTransactionId, WebAuthnMakeCredentialInfo aTransactionInfo);
     async RequestSign(uint64_t aTransactionId, WebAuthnGetAssertionInfo aTransactionInfo);
+    async RequestIsUVPAA() returns (bool available);
     [Tainted] async RequestCancel(uint64_t aTransactionId);
     async DestroyMe();
 
diff --git a/dom/webauthn/PublicKeyCredential.cpp b/dom/webauthn/PublicKeyCredential.cpp
index 4b8109d7b80c..bfcbeccda864 100644
--- a/dom/webauthn/PublicKeyCredential.cpp
+++ b/dom/webauthn/PublicKeyCredential.cpp
@@ -9,10 +9,13 @@
 #include "mozilla/Preferences.h"
 #include "mozilla/StaticPrefs_security.h"
 #include "mozilla/dom/AuthenticatorResponse.h"
+#include "mozilla/dom/CredentialsContainer.h"
 #include "mozilla/dom/ChromeUtils.h"
+#include "mozilla/dom/Navigator.h"
 #include "mozilla/dom/Promise.h"
 #include "mozilla/dom/PublicKeyCredential.h"
 #include "mozilla/dom/WebAuthenticationBinding.h"
+#include "mozilla/dom/WebAuthnManager.h"
 #include "nsCycleCollectionParticipant.h"
 
 #ifdef XP_WIN
@@ -117,46 +120,16 @@ void PublicKeyCredential::SetAssertionResponse(
 already_AddRefed<Promise>
 PublicKeyCredential::IsUserVerifyingPlatformAuthenticatorAvailable(
     GlobalObject& aGlobal, ErrorResult& aError) {
-  RefPtr<Promise> promise =
-      Promise::Create(xpc::CurrentNativeGlobal(aGlobal.Context()), aError);
-  if (aError.Failed()) {
+  nsCOMPtr<nsPIDOMWindowInner> window =
+      do_QueryInterface(aGlobal.GetAsSupports());
+  if (!window) {
+    aError.Throw(NS_ERROR_FAILURE);
     return nullptr;
   }
 
-// https://w3c.github.io/webauthn/#isUserVerifyingPlatformAuthenticatorAvailable
-//
-// If on latest windows, call system APIs, otherwise return false, as we don't
-// have other UVPAAs available at this time.
-#ifdef XP_WIN
-
-  if (WinWebAuthnService::IsUserVerifyingPlatformAuthenticatorAvailable()) {
-    promise->MaybeResolve(true);
-    return promise.forget();
-  }
-
-  promise->MaybeResolve(false);
-#elif defined(MOZ_WIDGET_ANDROID)
-  if (StaticPrefs::
-          security_webauthn_webauthn_enable_android_fido2_residentkey()) {
-    auto result = java::WebAuthnTokenManager::
-        WebAuthnIsUserVerifyingPlatformAuthenticatorAvailable();
-    auto geckoResult = java::GeckoResult::LocalRef(std::move(result));
-    MozPromise<bool, bool, false>::FromGeckoResult(geckoResult)
-        ->Then(
-            GetMainThreadSerialEventTarget(), __func__,
-            [promise](const MozPromise<bool, bool, false>::ResolveOrRejectValue&
-                          aValue) {
-              if (aValue.IsResolve()) {
-                promise->MaybeResolve(aValue.ResolveValue());
-              }
-            });
-  } else {
-    promise->MaybeResolve(false);
-  }
-#else
-  promise->MaybeResolve(false);
-#endif
-  return promise.forget();
+  RefPtr<WebAuthnManager> manager =
+      window->Navigator()->Credentials()->GetWebAuthnManager();
+  return manager->IsUVPAA(aGlobal, aError);
 }
 
 /* static */
diff --git a/dom/webauthn/WebAuthnManager.cpp b/dom/webauthn/WebAuthnManager.cpp
index 0236f36024ee..e7282b8a5cbb 100644
--- a/dom/webauthn/WebAuthnManager.cpp
+++ b/dom/webauthn/WebAuthnManager.cpp
@@ -18,6 +18,7 @@
 #include "mozilla/dom/PublicKeyCredential.h"
 #include "mozilla/dom/Promise.h"
 #include "mozilla/dom/PWebAuthnTransaction.h"
+#include "mozilla/dom/PWebAuthnTransactionChild.h"
 #include "mozilla/dom/WebAuthnManager.h"
 #include "mozilla/dom/WebAuthnTransactionChild.h"
 #include "mozilla/dom/WebAuthnUtil.h"
@@ -727,6 +728,32 @@ already_AddRefed<Promise> WebAuthnManager::Store(const Credential& aCredential,
   return promise.forget();
 }
 
+already_AddRefed<Promise> WebAuthnManager::IsUVPAA(GlobalObject& aGlobal,
+                                                   ErrorResult& aError) {
+  RefPtr<Promise> promise =
+      Promise::Create(xpc::CurrentNativeGlobal(aGlobal.Context()), aError);
+  if (aError.Failed()) {
+    return nullptr;
+  }
+
+  if (!MaybeCreateBackgroundActor()) {
+    promise->MaybeReject(NS_ERROR_DOM_OPERATION_ERR);
+    return promise.forget();
+  }
+
+  mChild->SendRequestIsUVPAA()->Then(
+      GetCurrentSerialEventTarget(), __func__,
+      [promise](const PWebAuthnTransactionChild::RequestIsUVPAAPromise::
+                    ResolveOrRejectValue& aValue) {
+        if (aValue.IsResolve()) {
+          promise->MaybeResolve(aValue.ResolveValue());
+        } else {
+          promise->MaybeReject(NS_ERROR_DOM_NOT_ALLOWED_ERR);
+        }
+      });
+  return promise.forget();
+}
+
 void WebAuthnManager::FinishMakeCredential(
     const uint64_t& aTransactionId,
     const WebAuthnMakeCredentialResult& aResult) {
diff --git a/dom/webauthn/WebAuthnManager.h b/dom/webauthn/WebAuthnManager.h
index 05175c8087cf..b0ccd7ccd418 100644
--- a/dom/webauthn/WebAuthnManager.h
+++ b/dom/webauthn/WebAuthnManager.h
@@ -95,6 +95,8 @@ class WebAuthnManager final : public WebAuthnManagerBase, public AbortFollower {
   already_AddRefed<Promise> Store(const Credential& aCredential,
                                   ErrorResult& aError);
 
+  already_AddRefed<Promise> IsUVPAA(GlobalObject& aGlobal, ErrorResult& aError);
+
   // WebAuthnManagerBase
 
   void FinishMakeCredential(
diff --git a/dom/webauthn/WebAuthnService.cpp b/dom/webauthn/WebAuthnService.cpp
index d8401698b7a7..70879f256cfa 100644
--- a/dom/webauthn/WebAuthnService.cpp
+++ b/dom/webauthn/WebAuthnService.cpp
@@ -40,6 +40,14 @@ WebAuthnService::GetAssertion(uint64_t aTransactionId,
                                         aArgs, aPromise);
 }
 
+NS_IMETHODIMP
+WebAuthnService::GetIsUVPAA(bool* aAvailable) {
+  if (StaticPrefs::security_webauth_webauthn_enable_softtoken()) {
+    return mTestService->GetIsUVPAA(aAvailable);
+  }
+  return mPlatformService->GetIsUVPAA(aAvailable);
+}
+
 NS_IMETHODIMP
 WebAuthnService::Reset() {
   if (StaticPrefs::security_webauth_webauthn_enable_softtoken()) {
diff --git a/dom/webauthn/WebAuthnTransactionParent.cpp b/dom/webauthn/WebAuthnTransactionParent.cpp
index 8ddd408baa55..f0de1b40dcff 100644
--- a/dom/webauthn/WebAuthnTransactionParent.cpp
+++ b/dom/webauthn/WebAuthnTransactionParent.cpp
@@ -280,6 +280,84 @@ mozilla::ipc::IPCResult WebAuthnTransactionParent::RecvRequestCancel(
   return IPC_OK();
 }
 
+mozilla::ipc::IPCResult WebAuthnTransactionParent::RecvRequestIsUVPAA(
+    RequestIsUVPAAResolver&& aResolver) {
+#ifdef MOZ_WIDGET_ANDROID
+  // Try the nsIWebAuthnService. If we're configured for tests we
+  // will get a result. Otherwise we expect NS_ERROR_NOT_IMPLEMENTED.
+  nsCOMPtr<nsIWebAuthnService> service(
+      do_GetService("@mozilla.org/webauthn/service;1"));
+  bool available;
+  nsresult rv = service->GetIsUVPAA(&available);
+  if (NS_SUCCEEDED(rv)) {
+    aResolver(available);
+    return IPC_OK();
+  }
+
+  // Don't consult the platform API if resident key support is disabled.
+  if (!StaticPrefs::
+          security_webauthn_webauthn_enable_android_fido2_residentkey()) {
+    aResolver(false);
+    return IPC_OK();
+  }
+
+  // The GeckoView implementation of
+  // isUserVerifiyingPlatformAuthenticatorAvailable does not block, but we must
+  // call it on the main thread. It returns a MozPromise which we can ->Then to
+  // call aResolver on the IPDL background thread.
+  //
+  // Bug 1550788: there is an unnecessary layer of dispatching here: ipdl ->
+  // main -> a background thread. Other platforms just do ipdl -> a background
+  // thread.
+  nsCOMPtr<nsISerialEventTarget> target = GetCurrentSerialEventTarget();
+  nsCOMPtr<nsIRunnable> runnable(NS_NewRunnableFunction(
+      __func__, [target, resolver = std::move(aResolver)]() {
+        auto result = java::WebAuthnTokenManager::
+            WebAuthnIsUserVerifyingPlatformAuthenticatorAvailable();
+        auto geckoResult = java::GeckoResult::LocalRef(std::move(result));
+        MozPromise<bool, bool, false>::FromGeckoResult(geckoResult)
+            ->Then(
+                target, __func__,
+                [resolver](
+                    const MozPromise<bool, bool, false>::ResolveOrRejectValue&
+                        aValue) {
+                  if (aValue.IsResolve()) {
+                    resolver(aValue.ResolveValue());
+                  } else {
+                    resolver(false);
+                  }
+                });
+      }));
+  NS_DispatchToMainThread(runnable.forget());
+  return IPC_OK();
+
+#else
+
+  nsCOMPtr<nsISerialEventTarget> target = GetCurrentSerialEventTarget();
+  nsCOMPtr<nsIRunnable> runnable(NS_NewRunnableFunction(
+      __func__, [target, resolver = std::move(aResolver)]() {
+        bool available;
+        nsCOMPtr<nsIWebAuthnService> service(
+            do_GetService("@mozilla.org/webauthn/service;1"));
+        nsresult rv = service->GetIsUVPAA(&available);
+        if (NS_FAILED(rv)) {
+          available = false;
+        }
+        BoolPromise::CreateAndResolve(available, __func__)
+            ->Then(target, __func__,
+                   [resolver](const BoolPromise::ResolveOrRejectValue& value) {
+                     if (value.IsResolve()) {
+                       resolver(value.ResolveValue());
+                     } else {
+                       resolver(false);
+                     }
+                   });
+      }));
+  NS_DispatchBackgroundTask(runnable.forget(), NS_DISPATCH_EVENT_MAY_BLOCK);
+  return IPC_OK();
+#endif
+}
+
 mozilla::ipc::IPCResult WebAuthnTransactionParent::RecvDestroyMe() {
   ::mozilla::ipc::AssertIsOnBackgroundThread();
 
diff --git a/dom/webauthn/WebAuthnTransactionParent.h b/dom/webauthn/WebAuthnTransactionParent.h
index f117f1bbdb46..3a119c9d57a1 100644
--- a/dom/webauthn/WebAuthnTransactionParent.h
+++ b/dom/webauthn/WebAuthnTransactionParent.h
@@ -35,6 +35,9 @@ class WebAuthnTransactionParent final : public PWebAuthnTransactionParent {
   mozilla::ipc::IPCResult RecvRequestCancel(
       const Tainted<uint64_t>& aTransactionId);
 
+  mozilla::ipc::IPCResult RecvRequestIsUVPAA(
+      RequestIsUVPAAResolver&& aResolver);
+
   mozilla::ipc::IPCResult RecvDestroyMe();
 
   virtual void ActorDestroy(ActorDestroyReason aWhy) override;
diff --git a/dom/webauthn/WinWebAuthnService.cpp b/dom/webauthn/WinWebAuthnService.cpp
index 9d6be22d1fb1..adb2c0e4b91a 100644
--- a/dom/webauthn/WinWebAuthnService.cpp
+++ b/dom/webauthn/WinWebAuthnService.cpp
@@ -132,18 +132,20 @@ bool WinWebAuthnService::AreWebAuthNApisAvailable() {
          gWinWebauthnGetApiVersionNumber() >= kMinWinWebAuthNApiVersion;
 }
 
-// static
-bool WinWebAuthnService::IsUserVerifyingPlatformAuthenticatorAvailable() {
+NS_IMETHODIMP
+WinWebAuthnService::GetIsUVPAA(bool* aAvailable) {
   nsresult rv = EnsureWinWebAuthnModuleLoaded();
-  NS_ENSURE_SUCCESS(rv, false);
+  NS_ENSURE_SUCCESS(rv, rv);
 
   if (WinWebAuthnService::AreWebAuthNApisAvailable()) {
     BOOL isUVPAA = FALSE;
     StaticAutoReadLock lock(gWinWebAuthnModuleLock);
-    return gWinWebAuthnModule && gWinWebauthnIsUVPAA(&isUVPAA) == S_OK &&
-           isUVPAA == TRUE;
+    *aAvailable = gWinWebAuthnModule && gWinWebauthnIsUVPAA(&isUVPAA) == S_OK &&
+                  isUVPAA == TRUE;
+  } else {
+    *aAvailable = false;
   }
-  return false;
+  return NS_OK;
 }
 
 NS_IMETHODIMP
diff --git a/dom/webauthn/authrs_bridge/src/lib.rs b/dom/webauthn/authrs_bridge/src/lib.rs
index e5cb09fe8c5b..69045a00d742 100644
--- a/dom/webauthn/authrs_bridge/src/lib.rs
+++ b/dom/webauthn/authrs_bridge/src/lib.rs
@@ -614,6 +614,17 @@ impl AuthrsService {
             .or(Err(NS_ERROR_FAILURE))
     }
 
+    xpcom_method!(get_is_uvpaa => GetIsUVPAA() -> bool);
+    fn get_is_uvpaa(&self) -> Result<bool, nsresult> {
+        if static_prefs::pref!("security.webauth.webauthn_enable_usbtoken") {
+            Ok(false)
+        } else if static_prefs::pref!("security.webauth.webauthn_enable_softtoken") {
+            Ok(self.test_token_manager.has_platform_authenticator())
+        } else {
+            Err(NS_ERROR_NOT_AVAILABLE)
+        }
+    }
+
     xpcom_method!(make_credential => MakeCredential(aTid: u64, aBrowsingContextId: u64, aArgs: *const nsIWebAuthnRegisterArgs, aPromise: *const nsIWebAuthnRegisterPromise));
     fn make_credential(
         &self,
diff --git a/dom/webauthn/authrs_bridge/src/test_token.rs b/dom/webauthn/authrs_bridge/src/test_token.rs
index bd0386143e3d..d7dc44c5bd05 100644
--- a/dom/webauthn/authrs_bridge/src/test_token.rs
+++ b/dom/webauthn/authrs_bridge/src/test_token.rs
@@ -870,4 +870,19 @@ impl TestTokenManager {
         .may_block(true)
         .dispatch_background_task();
     }
+
+    pub fn has_platform_authenticator(&self) -> bool {
+        if !static_prefs::pref!("security.webauth.webauthn_enable_softtoken") {
+            return false;
+        }
+
+        for token in self.state.lock().unwrap().values_mut() {
+            let _ = token.init();
+            if token.transport.as_str() == "internal" {
+                return true;
+            }
+        }
+
+        false
+    }
 }
diff --git a/dom/webauthn/nsIWebAuthnService.idl b/dom/webauthn/nsIWebAuthnService.idl
index cd46b809921b..15bd414bb5f6 100644
--- a/dom/webauthn/nsIWebAuthnService.idl
+++ b/dom/webauthn/nsIWebAuthnService.idl
@@ -22,6 +22,9 @@ interface nsICredentialParameters : nsISupports
 [scriptable, uuid(e236a9b4-a26f-11ed-b6cc-07a9834e19b1)]
 interface nsIWebAuthnService : nsISupports
 {
+    // IsUserVerifyingPlatformAuthenticatorAvailable
+    readonly attribute bool isUVPAA;
+
     void makeCredential(
         in uint64_t aTransactionId,
         in uint64_t browsingContextId,
diff --git a/dom/webauthn/tests/test_webauthn_isplatformauthenticatoravailable.html b/dom/webauthn/tests/test_webauthn_isplatformauthenticatoravailable.html
index e8ee1ba4536c..15b83659d512 100644
--- a/dom/webauthn/tests/test_webauthn_isplatformauthenticatoravailable.html
+++ b/dom/webauthn/tests/test_webauthn_isplatformauthenticatoravailable.html
@@ -18,19 +18,30 @@
 <script class="testbody" type="text/javascript">
 "use strict";
 
-add_task(async function test_is_platform_available() {
-  // This test ensures that isUserVerifyingPlatformAuthenticatorAvailable()
-  // is a callable method, but with the softtoken enabled, it's not useful to
-  // figure out what it actually returns, so we'll just make sure it runs.
-  await PublicKeyCredential.isUserVerifyingPlatformAuthenticatorAvailable()
-  .then(function(aResult) {
-    ok(true, "Resolved: " + aResult);
-  })
-  .catch(function(aProblem) {
-    ok(false, "Problem encountered: " + aProblem);
-  });
+add_task(async function test_uvpaa_with_no_authenticator() {
+  let uvpaa = await PublicKeyCredential.isUserVerifyingPlatformAuthenticatorAvailable();
+  ok(uvpaa === false, "Platform authenticator is not available");
 });
 
+add_task(async () => {
+  await addVirtualAuthenticator("ctap2_1", "usb");
+});
+
+add_task(async function test_uvpaa_with_usb_authenticator() {
+  let uvpaa = await PublicKeyCredential.isUserVerifyingPlatformAuthenticatorAvailable();
+  ok(uvpaa === false, "Platform authenticator is not available");
+});
+
+add_task(async () => {
+  await addVirtualAuthenticator("ctap2_1", "internal");
+});
+
+add_task(async function test_uvpaa_with_usb_and_platform_authenticator() {
+  let uvpaa = await PublicKeyCredential.isUserVerifyingPlatformAuthenticatorAvailable();
+  ok(uvpaa === true, "Platform authenticator is available");
+});
+
+
 </script>
 
 </body>
diff --git a/dom/webauthn/tests/u2futil.js b/dom/webauthn/tests/u2futil.js
index 178284d8eda7..e8026e8e5999 100644
--- a/dom/webauthn/tests/u2futil.js
+++ b/dom/webauthn/tests/u2futil.js
@@ -20,21 +20,45 @@ var { AppConstants } = SpecialPowers.ChromeUtils.importESModule(
   "resource://gre/modules/AppConstants.sys.mjs"
 );
 
-async function addVirtualAuthenticator() {
-  let id = await SpecialPowers.spawnChrome([], () => {
-    let webauthnService = Cc["@mozilla.org/webauthn/service;1"].getService(
-      Ci.nsIWebAuthnService
-    );
-    let id = webauthnService.addVirtualAuthenticator(
-      "ctap2_1",
-      "internal",
-      true,
-      true,
-      true,
-      true
-    );
-    return id;
-  });
+async function addVirtualAuthenticator(
+  protocol = "ctap2_1",
+  transport = "internal",
+  hasResidentKey = true,
+  hasUserVerification = true,
+  isUserConsenting = true,
+  isUserVerified = true
+) {
+  let id = await SpecialPowers.spawnChrome(
+    [
+      protocol,
+      transport,
+      hasResidentKey,
+      hasUserVerification,
+      isUserConsenting,
+      isUserVerified,
+    ],
+    (
+      protocol,
+      transport,
+      hasResidentKey,
+      hasUserVerification,
+      isUserConsenting,
+      isUserVerified
+    ) => {
+      let webauthnService = Cc["@mozilla.org/webauthn/service;1"].getService(
+        Ci.nsIWebAuthnService
+      );
+      let id = webauthnService.addVirtualAuthenticator(
+        protocol,
+        transport,
+        hasResidentKey,
+        hasUserVerification,
+        isUserConsenting,
+        isUserVerified
+      );
+      return id;
+    }
+  );
 
   SimpleTest.registerCleanupFunction(async () => {
     await SpecialPowers.spawnChrome([id], id => {