diff --git a/devtools/client/framework/source-map-worker.js b/devtools/client/framework/source-map-worker.js
index c68732f38e..b6ac2c121f 100644
--- a/devtools/client/framework/source-map-worker.js
+++ b/devtools/client/framework/source-map-worker.js
@@ -23,6 +23,19 @@ function enableSourceMaps() {
 
 function _resolveSourceMapURL(source) {
   const { url = "", sourceMapURL = "" } = source;
+  
+  const UNSUPPORTED_PROTOCOLS = ["chrome://", "resource://"];
+  if (path.isURL(sourceMapURL) && UNSUPPORTED_PROTOCOLS.some(protocol => sourceMapURL.startsWith(protocol))) {
+    // If it's an internal protocol, don't allow it and return empty.
+    return "";
+  }
+  if (path.isURL(sourceMapURL) && sourceMapURL.startsWith("file://")) {
+    // Only allow file:// source maps from file:// docs
+    if (!url.startsWith("file://")) {
+      return "";
+    }
+  }
+  
   if (path.isURL(sourceMapURL) || url == "") {
     // If it's already a full URL or the source doesn't have a URL,
     // don't resolve anything.
diff --git a/dom/canvas/WebGLContextDraw.cpp b/dom/canvas/WebGLContextDraw.cpp
index 8e437a07f3..c0ba20301a 100644
--- a/dom/canvas/WebGLContextDraw.cpp
+++ b/dom/canvas/WebGLContextDraw.cpp
@@ -1066,6 +1066,15 @@ WebGLContext::DoFakeVertexAttrib0(const char* funcName, GLuint vertexCount)
         vertexCount = 1;
     }
 
+    if (gl->WorkAroundDriverBugs() && gl->Vendor() == gl::GLVendor::Nouveau) {
+      // Padded/strided to vec4, so 4x4bytes.
+      const auto effectiveVertAttribBytes = CheckedInt<int32_t>(vertexCount) * 4 * 4;
+      if (!effectiveVertAttribBytes.isValid()) {
+        ErrorOutOfMemory("`offset + count` too large for Mesa.");
+        return false;
+      }
+    }
+
     const auto whatDoesAttrib0Need = WhatDoesVertexAttrib0Need();
     if (MOZ_LIKELY(whatDoesAttrib0Need == WebGLVertexAttrib0Status::Default))
         return true;
diff --git a/js/src/jit/MIR.h b/js/src/jit/MIR.h
index 8fd777d3ee..a398ef3344 100644
--- a/js/src/jit/MIR.h
+++ b/js/src/jit/MIR.h
@@ -10113,7 +10113,7 @@ class MLoadTypedArrayElementHole
         return congruentIfOperandsEqual(other);
     }
     AliasSet getAliasSet() const override {
-        return AliasSet::Load(AliasSet::UnboxedElement);
+        return AliasSet::Load(AliasSet::UnboxedElement | AliasSet::ObjectFields);
     }
     bool canProduceFloat32() const override { return arrayType_ == Scalar::Float32; }
 
diff --git a/xpcom/threads/LazyIdleThread.cpp b/xpcom/threads/LazyIdleThread.cpp
index d74f515e87..c5c7a5f192 100644
--- a/xpcom/threads/LazyIdleThread.cpp
+++ b/xpcom/threads/LazyIdleThread.cpp
@@ -137,10 +137,15 @@ LazyIdleThread::EnsureThread()
     return NS_OK;
   }
 
-  MOZ_ASSERT(!mPendingEventCount, "Shouldn't have events yet!");
-  MOZ_ASSERT(!mIdleNotificationCount, "Shouldn't have idle events yet!");
-  MOZ_ASSERT(!mIdleTimer, "Should have killed this long ago!");
-  MOZ_ASSERT(!mThreadIsShuttingDown, "Should have cleared that!");
+#ifdef DEBUG
+  { // Lock scope
+    MutexAutoLock lock(mMutex);
+    MOZ_ASSERT(!mPendingEventCount, "Shouldn't have events yet!");
+    MOZ_ASSERT(!mIdleNotificationCount, "Shouldn't have idle events yet!");
+    MOZ_ASSERT(!mIdleTimer, "Should have killed this long ago!");
+    MOZ_ASSERT(!mThreadIsShuttingDown, "Should have cleared that!");
+  }
+#endif
 
   nsresult rv;
 
diff --git a/xpcom/threads/LazyIdleThread.h b/xpcom/threads/LazyIdleThread.h
index 460971c7a8..9d437171a7 100644
--- a/xpcom/threads/LazyIdleThread.h
+++ b/xpcom/threads/LazyIdleThread.h
@@ -152,9 +152,10 @@ private:
   nsCOMPtr<nsIThread> mThread;
 
   /**
-   * Protected by mMutex. Created when mThread has no pending events and fired
+   * Created when mThread has no pending events and fired
    * at mOwningThread. Any thread that dispatches to mThread will take ownership
    * of the timer and fire a separate cancel event to the owning thread.
+   * Only accessed from the owning thread.
    */
   nsCOMPtr<nsITimer> mIdleTimer;
 
diff --git a/xpcom/threads/nsProcessCommon.cpp b/xpcom/threads/nsProcessCommon.cpp
index e815ec9ea4..7d490c5952 100644
--- a/xpcom/threads/nsProcessCommon.cpp
+++ b/xpcom/threads/nsProcessCommon.cpp
@@ -280,10 +280,13 @@ nsProcess::ProcessComplete()
   }
 
   const char* topic;
-  if (mExitValue < 0) {
-    topic = "process-failed";
-  } else {
-    topic = "process-finished";
+  { // Lock scope
+    MutexAutoLock lock(mLock);
+    if (mExitValue < 0) {
+      topic = "process-failed";
+    } else {
+      topic = "process-finished";
+    }
   }
 
   mPid = -1;
@@ -412,8 +415,11 @@ nsProcess::RunProcess(bool aBlocking, char** aMyArgv, nsIObserver* aObserver,
     }
   }
 
-  mExitValue = -1;
-  mPid = -1;
+  {
+    MutexAutoLock lock(mLock);
+    mExitValue = -1;
+    mPid = -1;
+  }
 
 #if defined(PROCESSMODEL_WINAPI)
   BOOL retVal;
@@ -477,6 +483,7 @@ nsProcess::RunProcess(bool aBlocking, char** aMyArgv, nsIObserver* aObserver,
   mBlocking = aBlocking;
   if (aBlocking) {
     Monitor(this);
+    MutexAutoLock lock(mLock);
     if (mExitValue < 0) {
       return NS_ERROR_FILE_EXECUTION_FAILED;
     }
diff --git a/xpcom/threads/nsThreadPool.cpp b/xpcom/threads/nsThreadPool.cpp
index ec8f326719..2d852809ab 100644
--- a/xpcom/threads/nsThreadPool.cpp
+++ b/xpcom/threads/nsThreadPool.cpp
@@ -155,8 +155,6 @@ nsThreadPool::Run()
 {
   mThreadNaming.SetThreadPoolName(mName);
 
-  LOG(("THRD-P(%p) enter %s\n", this, mName.BeginReading()));
-
   nsCOMPtr<nsIThread> current;
   nsThreadManager::get().GetCurrentThread(getter_AddRefs(current));
 
@@ -169,6 +167,7 @@ nsThreadPool::Run()
   {
     MutexAutoLock lock(mMutex);
     listener = mListener;
+    LOG(("THRD-P(%p) enter %s\n", this, mName.BeginReading()));
   }
 
   if (listener) {
@@ -223,7 +222,12 @@ nsThreadPool::Run()
       }
     }
     if (event) {
-      LOG(("THRD-P(%p) %s running [%p]\n", this, mName.BeginReading(), event.get()));
+#ifdef DEBUG
+      {
+        MutexAutoLock lock(mMutex);
+        LOG(("THRD-P(%p) %s running [%p]\n", this, mName.BeginReading(), event.get()));
+      }
+#endif
       event->Run();
     }
   } while (!exitThread);
@@ -335,6 +339,7 @@ nsThreadPool::Shutdown()
 NS_IMETHODIMP
 nsThreadPool::GetThreadLimit(uint32_t* aValue)
 {
+  MutexAutoLock lock(mMutex);
   *aValue = mThreadLimit;
   return NS_OK;
 }
@@ -358,6 +363,7 @@ nsThreadPool::SetThreadLimit(uint32_t aValue)
 NS_IMETHODIMP
 nsThreadPool::GetIdleThreadLimit(uint32_t* aValue)
 {
+  MutexAutoLock lock(mMutex);
   *aValue = mIdleThreadLimit;
   return NS_OK;
 }
@@ -382,6 +388,7 @@ nsThreadPool::SetIdleThreadLimit(uint32_t aValue)
 NS_IMETHODIMP
 nsThreadPool::GetIdleThreadTimeout(uint32_t* aValue)
 {
+  MutexAutoLock lock(mMutex);
   *aValue = mIdleThreadTimeout;
   return NS_OK;
 }
@@ -438,11 +445,9 @@ nsThreadPool::SetListener(nsIThreadPoolListener* aListener)
 NS_IMETHODIMP
 nsThreadPool::SetName(const nsACString& aName)
 {
-  {
-    MutexAutoLock lock(mMutex);
-    if (mThreads.Count()) {
-      return NS_ERROR_NOT_AVAILABLE;
-    }
+  MutexAutoLock lock(mMutex);
+  if (mThreads.Count()) {
+    return NS_ERROR_NOT_AVAILABLE;
   }
 
   mName = aName;