diff --git a/dom/media/gmp/ChromiumCDMProxy.cpp b/dom/media/gmp/ChromiumCDMProxy.cpp
index 26d0475ad8980af1994e605f13b7411f1b3a4ef4..debcb71b6fcacdffb5b2b9f9f4078481f4b9f770 100644
--- a/dom/media/gmp/ChromiumCDMProxy.cpp
+++ b/dom/media/gmp/ChromiumCDMProxy.cpp
@@ -7,6 +7,7 @@
 #include "ChromiumCDMProxy.h"
 #include "ChromiumCDMCallbackProxy.h"
 #include "MediaResult.h"
+#include "mozilla/StaticPrefs_media.h"
 #include "mozilla/dom/MediaKeySession.h"
 #include "GMPUtils.h"
 #include "nsPrintfCString.h"
@@ -381,13 +382,19 @@ void ChromiumCDMProxy::NotifyOutputProtectionStatus(
   }
 
   uint32_t linkMask{};
-  uint32_t protectionMask{};  // Unused/always zeroed.
+  uint32_t protectionMask{};
   if (aCheckStatus == OutputProtectionCheckStatus::CheckSuccessful &&
       aCaptureStatus == OutputProtectionCaptureStatus::CapturePossilbe) {
     // The result indicates the capture is possible, so set the mask
     // to indicate this.
     linkMask |= cdm::OutputLinkTypes::kLinkTypeNetwork;
   }
+  // `kProtectionNone` can cause playback to stop if HDCP_V1 is required. Report
+  // HDCP protection if there's no potential capturing.
+  if (linkMask == cdm::OutputLinkTypes::kLinkTypeNone &&
+      StaticPrefs::media_widevine_hdcp_protection_mask()) {
+    protectionMask = cdm::OutputProtectionMethods::kProtectionHDCP;
+  }
   mGMPThread->Dispatch(NewRunnableMethod<bool, uint32_t, uint32_t>(
       "gmp::ChromiumCDMParent::NotifyOutputProtectionStatus", cdm,
       &gmp::ChromiumCDMParent::NotifyOutputProtectionStatus,
diff --git a/modules/libpref/init/StaticPrefList.yaml b/modules/libpref/init/StaticPrefList.yaml
index 12ed7cfb441fc581f2cb0c3e091a78186de800b9..d2e9414437f08f1d4666d6977acadd8f717be109 100644
--- a/modules/libpref/init/StaticPrefList.yaml
+++ b/modules/libpref/init/StaticPrefList.yaml
@@ -11151,6 +11151,13 @@
   value: true
   mirror: always
 
+# When this is true, the protection mask that Firefox replies to Widevine API
+# QueryOutputProtectionStatus is `kProtectionHDCP` when no potential capturing.
+- name: media.widevine.hdcp-protection-mask
+  type: RelaxedAtomicBool
+  value: true
+  mirror: always
+
 #---------------------------------------------------------------------------
 # Prefs starting with "midi."
 #---------------------------------------------------------------------------