diff --git a/engine/src/flutter/examples/example-scrollable.sky b/engine/src/flutter/examples/example-scrollable.sky
index 21bba40c07..cd5e60f91f 100644
--- a/engine/src/flutter/examples/example-scrollable.sky
+++ b/engine/src/flutter/examples/example-scrollable.sky
@@ -1,3 +1,4 @@
+#!mojo mojo:sky_viewer
 <!--
 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
diff --git a/engine/src/flutter/examples/file-browser.sky b/engine/src/flutter/examples/file-browser.sky
index f71672c36d..05d72dee48 100644
--- a/engine/src/flutter/examples/file-browser.sky
+++ b/engine/src/flutter/examples/file-browser.sky
@@ -1,3 +1,4 @@
+#!mojo mojo:sky_viewer
 <!--
 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
diff --git a/engine/src/flutter/examples/flights-app/index.sky b/engine/src/flutter/examples/flights-app/index.sky
index 31c55af1ef..94564be2e2 100644
--- a/engine/src/flutter/examples/flights-app/index.sky
+++ b/engine/src/flutter/examples/flights-app/index.sky
@@ -1,3 +1,4 @@
+#!mojo mojo:sky_viewer
 <sky>
   <import src="flights-app.sky" as="FlightsAppElement"/>
   <style>
diff --git a/engine/src/flutter/examples/fps-counter.sky b/engine/src/flutter/examples/fps-counter.sky
index d9e982041d..4e1c881bb1 100644
--- a/engine/src/flutter/examples/fps-counter.sky
+++ b/engine/src/flutter/examples/fps-counter.sky
@@ -1,3 +1,4 @@
+#!mojo mojo:sky_viewer
 <!--
 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
diff --git a/engine/src/flutter/examples/radio.sky b/engine/src/flutter/examples/radio.sky
index 3da67a0699..33a45d54f2 100644
--- a/engine/src/flutter/examples/radio.sky
+++ b/engine/src/flutter/examples/radio.sky
@@ -65,7 +65,7 @@ SKY MODULE - radio button and radio button group
              return child.name;
        return '';
      }
-     set value (name) { 
+     set value (name) {
        let children = this.getChildNodes();
        for (let child of children)
          if (child instanceof module.exports.RadioElement)
diff --git a/engine/src/flutter/examples/touch-demo.sky b/engine/src/flutter/examples/touch-demo.sky
index 2ac1395418..78b86d20b1 100644
--- a/engine/src/flutter/examples/touch-demo.sky
+++ b/engine/src/flutter/examples/touch-demo.sky
@@ -1,3 +1,4 @@
+#!mojo mojo:sky_viewer
 <sky>
 <import src="fps-counter.sky" />
 <style>