diff --git a/dom/media/gmp/widevine-adapter/WidevineAdapter.cpp b/dom/media/gmp/widevine-adapter/WidevineAdapter.cpp
index 328f7001aeb7..51dfec0b7f18 100644
--- a/dom/media/gmp/widevine-adapter/WidevineAdapter.cpp
+++ b/dom/media/gmp/widevine-adapter/WidevineAdapter.cpp
@@ -13,11 +13,14 @@
 #include "gmp-api/gmp-decryption.h"
 #include "gmp-api/gmp-video-codec.h"
 #include "gmp-api/gmp-platform.h"
+#include "mozilla/StaticPtr.h"
 
 static const GMPPlatformAPI* sPlatform = nullptr;
 
 namespace mozilla {
 
+StaticRefPtr<CDMWrapper> sCDMWrapper;
+
 GMPErr GMPGetCurrentTime(GMPTimestamp* aOutTime) {
   return sPlatform->getcurrenttime(aOutTime);
 }
@@ -88,19 +91,19 @@ WidevineAdapter::GMPGetAPI(const char* aAPIName,
                            void** aPluginAPI,
                            uint32_t aDecryptorId)
 {
-  Log("WidevineAdapter::GMPGetAPI(%s, 0x%p, 0x%p, %u) this=0x%p",
-      aAPIName, aHostAPI, aPluginAPI, this, aDecryptorId);
+  Log("WidevineAdapter::GMPGetAPI(%s, 0x%p, 0x%p) this=0x%p",
+      aAPIName, aHostAPI, aPluginAPI, this);
   if (!strcmp(aAPIName, GMP_API_DECRYPTOR)) {
-    if (WidevineDecryptor::GetInstance(aDecryptorId)) {
-      // We only support one CDM instance per PGMPDecryptor. Fail!
-      Log("WidevineAdapter::GMPGetAPI() Tried to create more than once CDM per IPDL actor! FAIL!");
+    if (sCDMWrapper) {
+      // We only support one CDM instance per GMP process. Fail!
+      Log("WidevineAdapter::GMPGetAPI() Tried to create more than once CDM per process! FAIL!");
       return GMPQuotaExceededErr;
     }
     auto create = reinterpret_cast<decltype(::CreateCdmInstance)*>(
       PR_FindFunctionSymbol(mLib, "CreateCdmInstance"));
     if (!create) {
-      Log("WidevineAdapter::GMPGetAPI(%s, 0x%p, 0x%p, %u) this=0x%p FAILED to find CreateCdmInstance",
-        aAPIName, aHostAPI, aPluginAPI, this, aDecryptorId);
+      Log("WidevineAdapter::GMPGetAPI(%s, 0x%p, 0x%p) this=0x%p FAILED to find CreateCdmInstance",
+        aAPIName, aHostAPI, aPluginAPI, this);
       return GMPGenericErr;
     }
 
@@ -113,24 +116,24 @@ WidevineAdapter::GMPGetAPI(const char* aAPIName,
              &GetCdmHost,
              decryptor));
     if (!cdm) {
-      Log("WidevineAdapter::GMPGetAPI(%s, 0x%p, 0x%p, %u) this=0x%p FAILED to create cdm",
-          aAPIName, aHostAPI, aPluginAPI, this, aDecryptorId);
+      Log("WidevineAdapter::GMPGetAPI(%s, 0x%p, 0x%p) this=0x%p FAILED to create cdm",
+          aAPIName, aHostAPI, aPluginAPI, this);
       return GMPGenericErr;
     }
     Log("cdm: 0x%x", cdm);
-    RefPtr<CDMWrapper> wrapper(new CDMWrapper(cdm));
-    decryptor->SetCDM(wrapper, aDecryptorId);
+    sCDMWrapper = new CDMWrapper(cdm);
+    decryptor->SetCDM(RefPtr<CDMWrapper>(sCDMWrapper));
     *aPluginAPI = decryptor;
 
   } else if (!strcmp(aAPIName, GMP_API_VIDEO_DECODER)) {
-    RefPtr<CDMWrapper> wrapper = WidevineDecryptor::GetInstance(aDecryptorId);
-    if (!wrapper) {
-      Log("WidevineAdapter::GMPGetAPI(%s, 0x%p, 0x%p, %u) this=0x%p No cdm for video decoder",
-          aAPIName, aHostAPI, aPluginAPI, thiss, aDecryptorId);
+    if (!sCDMWrapper) {
+      Log("WidevineAdapter::GMPGetAPI(%s, 0x%p, 0x%p) this=0x%p No cdm for video decoder",
+          aAPIName, aHostAPI, aPluginAPI, this);
       return GMPGenericErr;
     }
     *aPluginAPI = new WidevineVideoDecoder(static_cast<GMPVideoHost*>(aHostAPI),
-                                           wrapper);
+                                           RefPtr<CDMWrapper>(sCDMWrapper));
+
   }
   return *aPluginAPI ? GMPNoErr : GMPNotImplementedErr;
 }
diff --git a/dom/media/gmp/widevine-adapter/WidevineDecryptor.cpp b/dom/media/gmp/widevine-adapter/WidevineDecryptor.cpp
index 80e4f36aace3..1c43ba43a987 100644
--- a/dom/media/gmp/widevine-adapter/WidevineDecryptor.cpp
+++ b/dom/media/gmp/widevine-adapter/WidevineDecryptor.cpp
@@ -16,19 +16,6 @@ using namespace std;
 
 namespace mozilla {
 
-static map<uint32_t, RefPtr<CDMWrapper>> sDecryptors;
-
-/* static */
-RefPtr<CDMWrapper>
-WidevineDecryptor::GetInstance(uint32_t aInstanceId)
-{
-  auto itr = sDecryptors.find(aInstanceId);
-  if (itr != sDecryptors.end()) {
-    return itr->second;
-  }
-  return nullptr;
-}
-
 
 WidevineDecryptor::WidevineDecryptor()
   : mCallback(nullptr)
@@ -43,11 +30,9 @@ WidevineDecryptor::~WidevineDecryptor()
 }
 
 void
-WidevineDecryptor::SetCDM(RefPtr<CDMWrapper> aCDM, uint32_t aInstanceId)
+WidevineDecryptor::SetCDM(RefPtr<CDMWrapper> aCDM)
 {
   mCDM = aCDM;
-  mInstanceId = aInstanceId;
-  sDecryptors[mInstanceId] = aCDM;
 }
 
 void
@@ -225,12 +210,7 @@ void
 WidevineDecryptor::DecryptingComplete()
 {
   Log("WidevineDecryptor::DecryptingComplete() this=%p", this);
-  // Drop our references to the CDMWrapper. When any other references
-  // held elsewhere are dropped (for example references held by a
-  // WidevineVideoDecoder, or a runnable), the CDMWrapper destroys
-  // the CDM.
   mCDM = nullptr;
-  sDecryptors.erase(mInstanceId);
   mCallback = nullptr;
   Release();
 }
diff --git a/dom/media/gmp/widevine-adapter/WidevineDecryptor.h b/dom/media/gmp/widevine-adapter/WidevineDecryptor.h
index d5185192b581..68fc35cbc864 100644
--- a/dom/media/gmp/widevine-adapter/WidevineDecryptor.h
+++ b/dom/media/gmp/widevine-adapter/WidevineDecryptor.h
@@ -24,9 +24,7 @@ public:
 
   WidevineDecryptor();
 
-  void SetCDM(RefPtr<CDMWrapper> aCDM, uint32_t aDecryptorId);
-
-  static RefPtr<CDMWrapper> GetInstance(uint32_t aDecryptorId);
+  void SetCDM(RefPtr<CDMWrapper> aCDM);
 
   // GMPDecryptor
   void Init(GMPDecryptorCallback* aCallback,
@@ -126,7 +124,6 @@ private:
   std::map<uint32_t, uint32_t> mPromiseIdToNewSessionTokens;
   bool mDistinctiveIdentifierRequired = false;
   bool mPersistentStateRequired = false;
-  uint32_t mInstanceId = 0;
 };
 
 } // namespace mozilla