diff --git a/dom/ipc/ContentChild.cpp b/dom/ipc/ContentChild.cpp
index e857af3e6400..a155f0c22b96 100644
--- a/dom/ipc/ContentChild.cpp
+++ b/dom/ipc/ContentChild.cpp
@@ -3256,10 +3256,11 @@ mozilla::ipc::IPCResult
 ContentChild::RecvGetFilesResponse(const nsID& aUUID,
                                    const GetFilesResponseResult& aResult)
 {
-  GetFilesHelperChild* child = mGetFilesPendingRequests.GetWeak(aUUID);
+  RefPtr<GetFilesHelperChild> child;
+
   // This object can already been deleted in case DeleteGetFilesRequest has
   // been called when the response was sending by the parent.
-  if (!child) {
+  if (!mGetFilesPendingRequests.Remove(aUUID, getter_AddRefs(child))) {
     return IPC_OK();
   }
 
@@ -3279,8 +3280,6 @@ ContentChild::RecvGetFilesResponse(const nsID& aUUID,
 
     child->Finished(succeeded ? NS_OK : NS_ERROR_OUT_OF_MEMORY);
   }
-
-  mGetFilesPendingRequests.Remove(aUUID);
   return IPC_OK();
 }
 
diff --git a/modules/libpref/init/all.js b/modules/libpref/init/all.js
index 7ad0dfb81295..cc53de4d1e85 100644
--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -1554,6 +1554,7 @@ pref("network.protocol-handler.external.hcp", false);
 pref("network.protocol-handler.external.vbscript", false);
 pref("network.protocol-handler.external.javascript", false);
 pref("network.protocol-handler.external.data", false);
+pref("network.protocol-handler.external.mk", false);
 pref("network.protocol-handler.external.ms-help", false);
 pref("network.protocol-handler.external.shell", false);
 pref("network.protocol-handler.external.vnd.ms.radio", false);
diff --git a/xpcom/threads/TimerThread.cpp b/xpcom/threads/TimerThread.cpp
index 99a40d91b3c0..86ed65d9cd61 100644
--- a/xpcom/threads/TimerThread.cpp
+++ b/xpcom/threads/TimerThread.cpp
@@ -170,6 +170,7 @@ class nsTimerEvent final : public CancelableRunnable
   void operator delete(void* aPtr)
   {
     sAllocator->Free(aPtr);
+    sAllocatorUsers--;
     DeleteAllocatorIfNeeded();
   }
 
@@ -193,7 +194,6 @@ class nsTimerEvent final : public CancelableRunnable
   {
     MOZ_ASSERT(!sCanDeleteAllocator || sAllocatorUsers > 0,
                "This will result in us attempting to deallocate the nsTimerEvent allocator twice");
-    sAllocatorUsers--;
   }
 
   RefPtr<nsTimerImpl> mTimer;