diff --git a/dom/media/GraphDriver.h b/dom/media/GraphDriver.h
index 34eb35f467..8c01a70e73 100644
--- a/dom/media/GraphDriver.h
+++ b/dom/media/GraphDriver.h
@@ -120,6 +120,11 @@ public:
     return mNextDriver || mPreviousDriver;
   }
 
+  GraphDriver* NextDriver()
+  {
+    return mNextDriver;
+  }
+
   /**
    * If we are running a real time graph, get the current time stamp to schedule
    * video frames. This has to be reimplemented by real time drivers.
diff --git a/dom/media/MediaStreamGraph.cpp b/dom/media/MediaStreamGraph.cpp
index 54fbdc1345..edac40d06a 100644
--- a/dom/media/MediaStreamGraph.cpp
+++ b/dom/media/MediaStreamGraph.cpp
@@ -623,6 +623,7 @@ MediaStreamGraphImpl::UpdateStreamOrder()
     if (CurrentDriver()->AsAudioCallbackDriver()->IsStarted()) {
       if (mLifecycleState == LIFECYCLE_RUNNING) {
         SystemClockDriver* driver = new SystemClockDriver(this);
+        mMixer.RemoveCallback(CurrentDriver()->AsAudioCallbackDriver());
         CurrentDriver()->SwitchAtNextIteration(driver);
       }
     }
@@ -2357,6 +2358,7 @@ MediaStream::RunAfterPendingUpdates(nsCOMPtr<nsIRunnable> aRunnable)
   // runnable will run in finite time.
   if (!(graph->mRealtime || graph->mNonRealtimeProcessing)) {
     aRunnable->Run();
+    return;
   }
 
   class Message : public ControlMessage {
@@ -3255,7 +3257,6 @@ MediaStreamGraph::NotifyWhenGraphStarted(AudioNodeStream* aStream)
     }
     virtual void RunDuringShutdown()
     {
-      MOZ_ASSERT(false, "We should be reviving the graph?");
     }
   };
 
@@ -3395,15 +3396,21 @@ MediaStreamGraphImpl::ApplyAudioContextOperationImpl(AudioNodeStream* aStream,
   // If we have suspended the last AudioContext, and we don't have other
   // streams that have audio, this graph will automatically switch to a
   // SystemCallbackDriver, because it can't find a MediaStream that has an audio
-  // track. When resuming, force switching to an AudioCallbackDriver. It would
-  // have happened at the next iteration anyways, but doing this now save
-  // some time.
+  // track. When resuming, force switching to an AudioCallbackDriver (if we're
+  // not already switching). It would have happened at the next iteration
+  // anyways, but doing this now save some time.
   if (aOperation == AudioContextOperation::Resume) {
     if (!CurrentDriver()->AsAudioCallbackDriver()) {
-      AudioCallbackDriver* driver = new AudioCallbackDriver(this);
+      AudioCallbackDriver* driver;
+      if (CurrentDriver()->Switching()) {
+        MOZ_ASSERT(CurrentDriver()->NextDriver()->AsAudioCallbackDriver());
+        driver = CurrentDriver()->NextDriver()->AsAudioCallbackDriver();
+      } else {
+        driver = new AudioCallbackDriver(this);
+        mMixer.AddCallback(driver);
+        CurrentDriver()->SwitchAtNextIteration(driver);
+      }
       driver->EnqueueStreamAndPromiseForOperation(aStream, aPromise, aOperation);
-      mMixer.AddCallback(driver);
-      CurrentDriver()->SwitchAtNextIteration(driver);
     } else {
       // We are resuming a context, but we are already using an
       // AudioCallbackDriver, we can resolve the promise now.
@@ -3431,8 +3438,14 @@ MediaStreamGraphImpl::ApplyAudioContextOperationImpl(AudioNodeStream* aStream,
       CurrentDriver()->AsAudioCallbackDriver()->
         EnqueueStreamAndPromiseForOperation(aStream, aPromise, aOperation);
 
-      SystemClockDriver* driver = new SystemClockDriver(this);
-      CurrentDriver()->SwitchAtNextIteration(driver);
+      SystemClockDriver* driver;
+      if (CurrentDriver()->NextDriver()) {
+        MOZ_ASSERT(!CurrentDriver()->NextDriver()->AsAudioCallbackDriver());
+      } else {
+        driver = new SystemClockDriver(this);
+        mMixer.RemoveCallback(CurrentDriver()->AsAudioCallbackDriver());
+        CurrentDriver()->SwitchAtNextIteration(driver);
+      }
     } else {
       // We are closing or suspending an AudioContext, but something else is
       // using the audio stream, we can resolve the promise now.
diff --git a/dom/media/test/crashtests/audiocontext-double-suspend.html b/dom/media/test/crashtests/audiocontext-double-suspend.html
new file mode 100644
index 0000000000..98399549bd
--- /dev/null
+++ b/dom/media/test/crashtests/audiocontext-double-suspend.html
@@ -0,0 +1,5 @@
+<script>
+var ac = new AudioContext();
+ac.resume();
+ac.resume();
+</script>
diff --git a/dom/media/test/crashtests/crashtests.list b/dom/media/test/crashtests/crashtests.list
index 6b404d0f2c..985a9fcf76 100644
--- a/dom/media/test/crashtests/crashtests.list
+++ b/dom/media/test/crashtests/crashtests.list
@@ -77,6 +77,7 @@ load oscillator-ended-2.html
 load 1080986.html
 load 1122218.html
 load 1158427.html
+load audiocontext-double-suspend.html
 include ../../mediasource/test/crashtests/crashtests.list
 
 # This needs to run at the end to avoid leaking busted state into other tests.
diff --git a/netwerk/protocol/http/nsHttpChannel.cpp b/netwerk/protocol/http/nsHttpChannel.cpp
index 5c91fc49a9..8cbb074bcf 100644
--- a/netwerk/protocol/http/nsHttpChannel.cpp
+++ b/netwerk/protocol/http/nsHttpChannel.cpp
@@ -270,6 +270,21 @@ nsHttpChannel::Connect()
 
     LOG(("nsHttpChannel::Connect [this=%p]\n", this));
 
+    // Note that we are only setting the "Upgrade-Insecure-Requests" request
+    // header for *all* navigational requests instead of all requests as
+    // defined in the spec, see:
+    // https://www.w3.org/TR/upgrade-insecure-requests/#preference
+    nsContentPolicyType type = mLoadInfo ?
+                               mLoadInfo->GetExternalContentPolicyType() :
+                               nsIContentPolicy::TYPE_OTHER;
+
+    if (type == nsIContentPolicy::TYPE_DOCUMENT ||
+        type == nsIContentPolicy::TYPE_SUBDOCUMENT) {
+        rv = SetRequestHeader(NS_LITERAL_CSTRING("Upgrade-Insecure-Requests"),
+                              NS_LITERAL_CSTRING("1"), false);
+        NS_ENSURE_SUCCESS(rv, rv);
+    }
+
     // Even if we're in private browsing mode, we still enforce existing STS
     // data (it is read-only).
     // if the connection is not using SSL and either the exact host matches or