--- a/mozglue/baseprofiler/core/ProfileBufferEntry.cpp
+++ b/mozglue/baseprofiler/core/ProfileBufferEntry.cpp
@@ -297,29 +297,35 @@ void UniqueStacks::StreamStack(const Sta
 }
 
 void UniqueStacks::StreamNonJITFrame(const FrameKey& aFrame) {
   using NormalFrameData = FrameKey::NormalFrameData;
 
   enum Schema : uint32_t {
     LOCATION = 0,
     RELEVANT_FOR_JS = 1,
-    IMPLEMENTATION = 2,
-    OPTIMIZATIONS = 3,
-    LINE = 4,
-    COLUMN = 5,
-    CATEGORY = 6,
-    SUBCATEGORY = 7
+    INNER_WINDOW_ID = 2,
+    IMPLEMENTATION = 3,
+    OPTIMIZATIONS = 4,
+    LINE = 5,
+    COLUMN = 6,
+    CATEGORY = 7,
+    SUBCATEGORY = 8
   };
 
   AutoArraySchemaWriter writer(mFrameTableWriter, *mUniqueStrings);
 
   const NormalFrameData& data = aFrame.mData.as<NormalFrameData>();
   writer.StringElement(LOCATION, data.mLocation.c_str());
   writer.BoolElement(RELEVANT_FOR_JS, data.mRelevantForJS);
+
+  // It's okay to convert uint64_t to double here because DOM always creates IDs
+  // that are convertible to double.
+  writer.DoubleElement(INNER_WINDOW_ID, data.mInnerWindowID);
+
   if (data.mLine.isSome()) {
     writer.IntElement(LINE, *data.mLine);
   }
   if (data.mColumn.isSome()) {
     writer.IntElement(COLUMN, *data.mColumn);
   }
   if (data.mCategoryPair.isSome()) {
     const ProfilingCategoryPairInfo& info =

--- a/mozglue/baseprofiler/core/ProfileBufferEntry.h
+++ b/mozglue/baseprofiler/core/ProfileBufferEntry.h
@@ -360,22 +360,23 @@ class UniqueStacks {
 //   },
 //
 //   "frameTable":
 //   {
 //     "schema":
 //     {
 //       "location": 0,       /* index into stringTable */
 //       "relevantForJS": 1,  /* bool */
-//       "implementation": 2, /* index into stringTable */
-//       "optimizations": 3,  /* arbitrary JSON */
-//       "line": 4,           /* number */
-//       "column": 5,         /* number */
-//       "category": 6        /* index into profile.meta.categories */
-//       "subcategory": 7     /* index into
+//       "innerWindowID": 2,  /* inner window ID of global JS `window` object */
+//       "implementation": 3, /* index into stringTable */
+//       "optimizations": 4,  /* arbitrary JSON */
+//       "line": 5,           /* number */
+//       "column": 6,         /* number */
+//       "category": 7,       /* index into profile.meta.categories */
+//       "subcategory": 8     /* index into
 //       profile.meta.categories[category].subcategories */
 //     },
 //     "data":
 //     [
 //       [ 0 ],               /* { location: '(root)' } */
 //       [ 1, 2 ]             /* { location: 'foo.js',
 //                                 implementation: 'baseline' } */
 //     ]

--- a/mozglue/baseprofiler/core/ProfiledThreadData.cpp
+++ b/mozglue/baseprofiler/core/ProfiledThreadData.cpp
@@ -54,16 +54,17 @@ void ProfiledThreadData::StreamJSON(cons
     aWriter.EndObject();
 
     aWriter.StartObjectProperty("frameTable");
     {
       {
         JSONSchemaWriter schema(aWriter);
         schema.WriteField("location");
         schema.WriteField("relevantForJS");
+        schema.WriteField("innerWindowID");
         schema.WriteField("implementation");
         schema.WriteField("optimizations");
         schema.WriteField("line");
         schema.WriteField("column");
         schema.WriteField("category");
         schema.WriteField("subcategory");
       }
 

--- a/mozglue/baseprofiler/core/platform.cpp
+++ b/mozglue/baseprofiler/core/platform.cpp
@@ -1615,17 +1615,17 @@ static void StreamCategories(SpliceableJ
 
 static int64_t MicrosecondsSince1970();
 
 static void StreamMetaJSCustomObject(PSLockRef aLock,
                                      SpliceableJSONWriter& aWriter,
                                      bool aIsShuttingDown) {
   MOZ_RELEASE_ASSERT(CorePS::Exists() && ActivePS::Exists(aLock));
 
-  aWriter.IntProperty("version", 18);
+  aWriter.IntProperty("version", 19);
 
   // The "startTime" field holds the number of milliseconds since midnight
   // January 1, 1970 GMT. This grotty code computes (Now - (Now -
   // ProcessStartTime)) to convert CorePS::ProcessStartTime() into that form.
   TimeDuration delta = TimeStamp::NowUnfuzzed() - CorePS::ProcessStartTime();
   aWriter.DoubleProperty(
       "startTime", MicrosecondsSince1970() / 1000.0 - delta.ToMilliseconds());
 

--- a/tools/profiler/core/ProfileBufferEntry.cpp
+++ b/tools/profiler/core/ProfileBufferEntry.cpp
@@ -458,29 +458,35 @@ void UniqueStacks::StreamStack(const Sta
 }
 
 void UniqueStacks::StreamNonJITFrame(const FrameKey& aFrame) {
   using NormalFrameData = FrameKey::NormalFrameData;
 
   enum Schema : uint32_t {
     LOCATION = 0,
     RELEVANT_FOR_JS = 1,
-    IMPLEMENTATION = 2,
-    OPTIMIZATIONS = 3,
-    LINE = 4,
-    COLUMN = 5,
-    CATEGORY = 6,
-    SUBCATEGORY = 7
+    INNER_WINDOW_ID = 2,
+    IMPLEMENTATION = 3,
+    OPTIMIZATIONS = 4,
+    LINE = 5,
+    COLUMN = 6,
+    CATEGORY = 7,
+    SUBCATEGORY = 8
   };
 
   AutoArraySchemaWriter writer(mFrameTableWriter, *mUniqueStrings);
 
   const NormalFrameData& data = aFrame.mData.as<NormalFrameData>();
   writer.StringElement(LOCATION, data.mLocation.get());
   writer.BoolElement(RELEVANT_FOR_JS, data.mRelevantForJS);
+
+  // It's okay to convert uint64_t to double here because DOM always creates IDs
+  // that are convertible to double.
+  writer.DoubleElement(INNER_WINDOW_ID, data.mInnerWindowID);
+
   if (data.mLine.isSome()) {
     writer.IntElement(LINE, *data.mLine);
   }
   if (data.mColumn.isSome()) {
     writer.IntElement(COLUMN, *data.mColumn);
   }
   if (data.mCategoryPair.isSome()) {
     const JS::ProfilingCategoryPairInfo& info =
@@ -579,29 +585,35 @@ static void StreamJITFrameOptimizations(
 }
 
 static void StreamJITFrame(JSContext* aContext, SpliceableJSONWriter& aWriter,
                            UniqueJSONStrings& aUniqueStrings,
                            const JS::ProfiledFrameHandle& aJITFrame) {
   enum Schema : uint32_t {
     LOCATION = 0,
     RELEVANT_FOR_JS = 1,
-    IMPLEMENTATION = 2,
-    OPTIMIZATIONS = 3,
-    LINE = 4,
-    COLUMN = 5,
-    CATEGORY = 6,
-    SUBCATEGORY = 7
+    INNER_WINDOW_ID = 2,
+    IMPLEMENTATION = 3,
+    OPTIMIZATIONS = 4,
+    LINE = 5,
+    COLUMN = 6,
+    CATEGORY = 7,
+    SUBCATEGORY = 8
   };
 
   AutoArraySchemaWriter writer(aWriter, aUniqueStrings);
 
   writer.StringElement(LOCATION, aJITFrame.label());
   writer.BoolElement(RELEVANT_FOR_JS, false);
 
+  // It's okay to convert uint64_t to double here because DOM always creates IDs
+  // that are convertible to double.
+  // Realm ID is the name of innerWindowID inside JS code.
+  writer.DoubleElement(INNER_WINDOW_ID, aJITFrame.realmID());
+
   JS::ProfilingFrameIterator::FrameKind frameKind = aJITFrame.frameKind();
   MOZ_ASSERT(frameKind == JS::ProfilingFrameIterator::Frame_Ion ||
              frameKind == JS::ProfilingFrameIterator::Frame_Baseline);
   writer.StringElement(
       IMPLEMENTATION,
       frameKind == JS::ProfilingFrameIterator::Frame_Ion ? "ion" : "baseline");
 
   if (aJITFrame.hasTrackedOptimizations()) {

--- a/tools/profiler/core/ProfileBufferEntry.h
+++ b/tools/profiler/core/ProfileBufferEntry.h
@@ -497,22 +497,23 @@ class UniqueStacks {
 //   },
 //
 //   "frameTable":
 //   {
 //     "schema":
 //     {
 //       "location": 0,       /* index into stringTable */
 //       "relevantForJS": 1,  /* bool */
-//       "implementation": 2, /* index into stringTable */
-//       "optimizations": 3,  /* arbitrary JSON */
-//       "line": 4,           /* number */
-//       "column": 5,         /* number */
-//       "category": 6        /* index into profile.meta.categories */
-//       "subcategory": 7     /* index into
+//       "innerWindowID": 2,  /* inner window ID of global JS `window` object */
+//       "implementation": 3, /* index into stringTable */
+//       "optimizations": 4,  /* arbitrary JSON */
+//       "line": 5,           /* number */
+//       "column": 6,         /* number */
+//       "category": 7,       /* index into profile.meta.categories */
+//       "subcategory": 8     /* index into
 //       profile.meta.categories[category].subcategories */
 //     },
 //     "data":
 //     [
 //       [ 0 ],               /* { location: '(root)' } */
 //       [ 1, 2 ]             /* { location: 'foo.js',
 //                                 implementation: 'baseline' } */
 //     ]

--- a/tools/profiler/core/ProfiledThreadData.cpp
+++ b/tools/profiler/core/ProfiledThreadData.cpp
@@ -76,16 +76,17 @@ void ProfiledThreadData::StreamJSON(cons
     aWriter.EndObject();
 
     aWriter.StartObjectProperty("frameTable");
     {
       {
         JSONSchemaWriter schema(aWriter);
         schema.WriteField("location");
         schema.WriteField("relevantForJS");
+        schema.WriteField("innerWindowID");
         schema.WriteField("implementation");
         schema.WriteField("optimizations");
         schema.WriteField("line");
         schema.WriteField("column");
         schema.WriteField("category");
         schema.WriteField("subcategory");
       }
 

--- a/tools/profiler/core/platform.cpp
+++ b/tools/profiler/core/platform.cpp
@@ -2042,17 +2042,17 @@ static void StreamCategories(SpliceableJ
 #undef CATEGORY_JSON_END_CATEGORY
 }
 
 static void StreamMetaJSCustomObject(PSLockRef aLock,
                                      SpliceableJSONWriter& aWriter,
                                      bool aIsShuttingDown) {
   MOZ_RELEASE_ASSERT(CorePS::Exists() && ActivePS::Exists(aLock));
 
-  aWriter.IntProperty("version", 18);
+  aWriter.IntProperty("version", 19);
 
   // The "startTime" field holds the number of milliseconds since midnight
   // January 1, 1970 GMT. This grotty code computes (Now - (Now -
   // ProcessStartTime)) to convert CorePS::ProcessStartTime() into that form.
   TimeDuration delta = TimeStamp::NowUnfuzzed() - CorePS::ProcessStartTime();
   aWriter.DoubleProperty(
       "startTime",
       static_cast<double>(PR_Now() / 1000.0 - delta.ToMilliseconds()));