diff --git a/docshell/base/CanonicalBrowsingContext.cpp b/docshell/base/CanonicalBrowsingContext.cpp
index 6048a2c0e8eb..5cd83a13645f 100644
--- a/docshell/base/CanonicalBrowsingContext.cpp
+++ b/docshell/base/CanonicalBrowsingContext.cpp
@@ -184,9 +184,6 @@ ContentParent* CanonicalBrowsingContext::GetContentParent() const {
   }
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (!cpm) {
-    return nullptr;
-  }
   return cpm->GetContentProcessById(ContentParentId(mProcessId));
 }
 
diff --git a/dom/base/nsFrameLoader.cpp b/dom/base/nsFrameLoader.cpp
index 0ebd25360dbb..c558a14c97c4 100644
--- a/dom/base/nsFrameLoader.cpp
+++ b/dom/base/nsFrameLoader.cpp
@@ -2750,9 +2750,6 @@ bool nsFrameLoader::TryRemoteBrowserInternal() {
     RefPtr<ContentParent> contentParent;
     if (mChildID != 0) {
       ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-      if (cpm) {
-        return false;
-      }
       contentParent = cpm->GetContentProcessById(ContentParentId(mChildID));
     }
     mRemoteBrowser =
diff --git a/dom/ipc/BrowserBridgeParent.cpp b/dom/ipc/BrowserBridgeParent.cpp
index e856864748ce..1039f6e24720 100644
--- a/dom/ipc/BrowserBridgeParent.cpp
+++ b/dom/ipc/BrowserBridgeParent.cpp
@@ -83,9 +83,6 @@ nsresult BrowserBridgeParent::InitWithProcess(
   }
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (!cpm) {
-    return NS_ERROR_UNEXPECTED;
-  }
   cpm->RegisterRemoteFrame(browserParent);
 
   RefPtr<WindowGlobalParent> windowParent =
diff --git a/dom/ipc/BrowserParent.cpp b/dom/ipc/BrowserParent.cpp
index 45eb3de92a23..57cd0a5f64e4 100644
--- a/dom/ipc/BrowserParent.cpp
+++ b/dom/ipc/BrowserParent.cpp
@@ -675,10 +675,7 @@ mozilla::ipc::IPCResult BrowserParent::RecvEnsureLayersConnected(
 void BrowserParent::ActorDestroy(ActorDestroyReason why) {
   Manager()->NotifyTabDestroyed(mTabId, mMarkedDestroying);
 
-  ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (cpm) {
-    cpm->UnregisterRemoteFrame(mTabId);
-  }
+  ContentProcessManager::GetSingleton()->UnregisterRemoteFrame(mTabId);
 
   if (mRemoteLayerTreeOwner.IsInitialized()) {
     auto layersId = mRemoteLayerTreeOwner.GetLayersId();
diff --git a/dom/ipc/ContentParent.cpp b/dom/ipc/ContentParent.cpp
index 87fbc45ef51d..e694f441ee36 100644
--- a/dom/ipc/ContentParent.cpp
+++ b/dom/ipc/ContentParent.cpp
@@ -1530,9 +1530,6 @@ already_AddRefed<RemoteBrowser> ContentParent::CreateBrowser(
   }
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (NS_WARN_IF(!cpm)) {
-    return nullptr;
-  }
   cpm->RegisterRemoteFrame(browserParent);
 
   nsCOMPtr<nsIPrincipal> initialPrincipal =
@@ -2093,9 +2090,7 @@ void ContentParent::ActorDestroy(ActorDestroyReason why) {
   mSubprocess = nullptr;
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (cpm) {
-    cpm->RemoveContentProcess(this->ChildID());
-  }
+  cpm->RemoveContentProcess(this->ChildID());
 
   if (mDriverCrashGuard) {
     mDriverCrashGuard->NotifyCrashed();
@@ -2486,8 +2481,6 @@ void ContentParent::AppendSandboxParams(std::vector<std::string>& aArgs) {
 bool ContentParent::BeginSubprocessLaunch(ProcessPriority aPriority) {
   AUTO_PROFILER_LABEL("ContentParent::LaunchSubprocess", OTHER);
 
-  // XXX: This check works only late, as GetSingleton will return nullptr
-  // only after ClearOnShutdown happened. See bug 1632740.
   if (!ContentProcessManager::GetSingleton()) {
     NS_WARNING(
         "Shutdown has begun, we shouldn't spawn any more child processes");
@@ -2620,13 +2613,7 @@ bool ContentParent::LaunchSubprocessResolve(bool aIsSync,
       base::GetProcId(mSubprocess->GetChildProcessHandle());
   Open(mSubprocess->TakeInitialPort(), procId);
 
-  ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (!cpm) {
-    NS_WARNING("immediately shutting-down caused by our shutdown");
-    ShutDownProcess(SEND_SHUTDOWN_MESSAGE);
-    return false;
-  }
-  cpm->AddContentProcess(this);
+  ContentProcessManager::GetSingleton()->AddContentProcess(this);
 
 #ifdef MOZ_CODE_COVERAGE
   Unused << SendShareCodeCoverageMutex(
@@ -4039,7 +4026,7 @@ mozilla::ipc::IPCResult ContentParent::RecvConstructPopupBrowser(
     // window.open().
     // We need to register remote frame with the child generated tab id.
     auto* cpm = ContentProcessManager::GetSingleton();
-    if (!cpm || !cpm->RegisterRemoteFrame(parent)) {
+    if (!cpm->RegisterRemoteFrame(parent)) {
       return IPC_FAIL(this, "RegisterRemoteFrame Failed");
     }
   }
@@ -5169,12 +5156,9 @@ ContentParent::AllocPContentPermissionRequestParent(
     const IPC::Principal& aPrincipal, const IPC::Principal& aTopLevelPrincipal,
     const bool& aIsHandlingUserInput,
     const bool& aMaybeUnsafePermissionDelegate, const TabId& aTabId) {
-  RefPtr<BrowserParent> tp;
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (cpm) {
-    tp =
-        cpm->GetTopLevelBrowserParentByProcessAndTabId(this->ChildID(), aTabId);
-  }
+  RefPtr<BrowserParent> tp =
+      cpm->GetTopLevelBrowserParentByProcessAndTabId(this->ChildID(), aTabId);
   if (!tp) {
     return nullptr;
   }
@@ -6828,11 +6812,9 @@ mozilla::ipc::IPCResult ContentParent::RecvWindowClose(
   //       browsing contexts of bc.
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (cpm) {
-    ContentParent* cp =
-        cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
-    Unused << cp->SendWindowClose(context, aTrustedCaller);
-  }
+  ContentParent* cp =
+      cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
+  Unused << cp->SendWindowClose(context, aTrustedCaller);
   return IPC_OK();
 }
 
@@ -6849,11 +6831,9 @@ mozilla::ipc::IPCResult ContentParent::RecvWindowFocus(
   CanonicalBrowsingContext* context = aContext.get_canonical();
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (cpm) {
-    ContentParent* cp =
-        cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
-    Unused << cp->SendWindowFocus(context, aCallerType, aActionId);
-  }
+  ContentParent* cp =
+      cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
+  Unused << cp->SendWindowFocus(context, aCallerType, aActionId);
   return IPC_OK();
 }
 
@@ -6868,11 +6848,9 @@ mozilla::ipc::IPCResult ContentParent::RecvWindowBlur(
   CanonicalBrowsingContext* context = aContext.get_canonical();
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (cpm) {
-    ContentParent* cp =
-        cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
-    Unused << cp->SendWindowBlur(context, aCallerType);
-  }
+  ContentParent* cp =
+      cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
+  Unused << cp->SendWindowBlur(context, aCallerType);
   return IPC_OK();
 }
 
@@ -6890,11 +6868,9 @@ mozilla::ipc::IPCResult ContentParent::RecvRaiseWindow(
   CanonicalBrowsingContext* context = aContext.get_canonical();
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (cpm) {
-    ContentParent* cp =
-        cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
-    Unused << cp->SendRaiseWindow(context, aCallerType, aActionId);
-  }
+  ContentParent* cp =
+      cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
+  Unused << cp->SendRaiseWindow(context, aCallerType, aActionId);
   return IPC_OK();
 }
 
@@ -6915,23 +6891,21 @@ mozilla::ipc::IPCResult ContentParent::RecvAdjustWindowFocus(
   processes.InsertOrUpdate(this, true);
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (cpm) {
-    CanonicalBrowsingContext* context = aContext.get_canonical();
-    while (context) {
-      BrowsingContext* parent = context->GetParent();
-      if (!parent) {
-        break;
-      }
-
-      CanonicalBrowsingContext* canonicalParent = parent->Canonical();
-      ContentParent* cp = cpm->GetContentProcessById(
-          ContentParentId(canonicalParent->OwnerProcessId()));
-      if (cp && !processes.Get(cp)) {
-        Unused << cp->SendAdjustWindowFocus(context, aIsVisible, aActionId);
-        processes.InsertOrUpdate(cp, true);
-      }
-      context = canonicalParent;
+  CanonicalBrowsingContext* context = aContext.get_canonical();
+  while (context) {
+    BrowsingContext* parent = context->GetParent();
+    if (!parent) {
+      break;
     }
+
+    CanonicalBrowsingContext* canonicalParent = parent->Canonical();
+    ContentParent* cp = cpm->GetContentProcessById(
+        ContentParentId(canonicalParent->OwnerProcessId()));
+    if (cp && !processes.Get(cp)) {
+      Unused << cp->SendAdjustWindowFocus(context, aIsVisible, aActionId);
+      processes.InsertOrUpdate(cp, true);
+    }
+    context = canonicalParent;
   }
   return IPC_OK();
 }
@@ -6947,11 +6921,9 @@ mozilla::ipc::IPCResult ContentParent::RecvClearFocus(
   CanonicalBrowsingContext* context = aContext.get_canonical();
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (cpm) {
-    ContentParent* cp =
-        cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
-    Unused << cp->SendClearFocus(context);
-  }
+  ContentParent* cp =
+      cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
+  Unused << cp->SendClearFocus(context);
   return IPC_OK();
 }
 
@@ -7074,11 +7046,11 @@ mozilla::ipc::IPCResult ContentParent::RecvSetFocusedElement(
   CanonicalBrowsingContext* context = aContext.get_canonical();
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (cpm) {
-    ContentParent* cp =
-        cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
-    Unused << cp->SendSetFocusedElement(context, aNeedsFocus);
-  }
+
+  ContentParent* cp =
+      cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
+  Unused << cp->SendSetFocusedElement(context, aNeedsFocus);
+
   return IPC_OK();
 }
 
@@ -7094,12 +7066,11 @@ mozilla::ipc::IPCResult ContentParent::RecvFinalizeFocusOuter(
   LOGFOCUS(("ContentParent::RecvFinalizeFocusOuter"));
   CanonicalBrowsingContext* context = aContext.get_canonical();
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (cpm) {
-    ContentParent* cp = cpm->GetContentProcessById(
-        ContentParentId(context->EmbedderProcessId()));
-    if (cp) {
-      Unused << cp->SendFinalizeFocusOuter(context, aCanFocus, aCallerType);
-    }
+
+  ContentParent* cp =
+      cpm->GetContentProcessById(ContentParentId(context->EmbedderProcessId()));
+  if (cp) {
+    Unused << cp->SendFinalizeFocusOuter(context, aCanFocus, aCallerType);
   }
   return IPC_OK();
 }
@@ -7140,9 +7111,6 @@ mozilla::ipc::IPCResult ContentParent::RecvBlurToParent(
       aFocusedBrowsingContext.get_canonical();
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (!cpm) {
-    return IPC_OK();
-  }
 
   // If aBrowsingContextToClear and aAncestorBrowsingContextToFocusHandled
   // didn't get handled in the process that sent this IPC message and they
@@ -7190,11 +7158,10 @@ mozilla::ipc::IPCResult ContentParent::RecvMaybeExitFullscreen(
   CanonicalBrowsingContext* context = aContext.get_canonical();
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
-  if (cpm) {
-    ContentParent* cp =
-        cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
-    Unused << cp->SendMaybeExitFullscreen(context);
-  }
+
+  ContentParent* cp =
+      cpm->GetContentProcessById(ContentParentId(context->OwnerProcessId()));
+  Unused << cp->SendMaybeExitFullscreen(context);
 
   return IPC_OK();
 }
diff --git a/dom/media/webrtc/transport/ipc/WebrtcTCPSocket.cpp b/dom/media/webrtc/transport/ipc/WebrtcTCPSocket.cpp
index d33c9a1dd865..26a883cece75 100644
--- a/dom/media/webrtc/transport/ipc/WebrtcTCPSocket.cpp
+++ b/dom/media/webrtc/transport/ipc/WebrtcTCPSocket.cpp
@@ -73,10 +73,8 @@ WebrtcTCPSocket::~WebrtcTCPSocket() {
 void WebrtcTCPSocket::SetTabId(dom::TabId aTabId) {
   MOZ_ASSERT(NS_IsMainThread());
   dom::ContentProcessManager* cpm = dom::ContentProcessManager::GetSingleton();
-  if (cpm) {
-    dom::ContentParentId cpId = cpm->GetTabProcessId(aTabId);
-    mAuthProvider = cpm->GetBrowserParentByProcessAndTabId(cpId, aTabId);
-  }
+  dom::ContentParentId cpId = cpm->GetTabProcessId(aTabId);
+  mAuthProvider = cpm->GetBrowserParentByProcessAndTabId(cpId, aTabId);
 }
 
 nsresult WebrtcTCPSocket::Write(nsTArray<uint8_t>&& aWriteData) {
diff --git a/gfx/ipc/CrossProcessPaint.cpp b/gfx/ipc/CrossProcessPaint.cpp
index 23eafc408f03..608fb30af425 100644
--- a/gfx/ipc/CrossProcessPaint.cpp
+++ b/gfx/ipc/CrossProcessPaint.cpp
@@ -367,18 +367,13 @@ void CrossProcessPaint::LostFragment(dom::WindowGlobalParent* aWGP) {
 
 void CrossProcessPaint::QueueDependencies(
     const nsTHashSet<uint64_t>& aDependencies) {
-  dom::ContentProcessManager* cpm = dom::ContentProcessManager::GetSingleton();
-  if (!cpm) {
-    CPP_LOG(
-        "Skipping QueueDependencies with no"
-        " current ContentProcessManager.\n");
-    return;
-  }
   for (const auto& key : aDependencies) {
     auto dependency = dom::TabId(key);
 
     // Get the current BrowserParent of the remote browser that was marked
     // as a dependency
+    dom::ContentProcessManager* cpm =
+        dom::ContentProcessManager::GetSingleton();
     dom::ContentParentId cpId = cpm->GetTabProcessId(dependency);
     RefPtr<dom::BrowserParent> browser =
         cpm->GetBrowserParentByProcessAndTabId(cpId, dependency);