--- a/testing/marionette/driver.js
+++ b/testing/marionette/driver.js
@@ -149,17 +149,16 @@ this.GeckoDriver = function(appName, ser
 
     // Selenium 2 compat
     "platform": Services.sysinfo.getProperty("name").toUpperCase(),
 
     // proprietary extensions
     "XULappId" : Services.appinfo.ID,
     "appBuildId" : Services.appinfo.appBuildID,
     "processId" : Services.appinfo.processID,
-    "version": Services.appinfo.version,
   };
 
   this.mm = globalMessageManager;
   this.listener = proxy.toListener(() => this.mm, this.sendAsync.bind(this));
 
   // always keep weak reference to current dialogue
   this.dialog = null;
   let handleDialog = (subject, topic) => {

--- a/testing/marionette/harness/marionette/tests/unit/test_capabilities.py
+++ b/testing/marionette/harness/marionette/tests/unit/test_capabilities.py
@@ -44,21 +44,19 @@ class TestCapabilities(MarionetteTestCas
 
     def test_selenium2_compat(self):
         self.assertIn("platform", self.caps)
         self.assertEqual(self.caps["platform"], self.caps["platformName"].upper())
 
     def test_extensions(self):
         self.assertIn("XULappId", self.caps)
         self.assertIn("appBuildId", self.caps)
-        self.assertIn("version", self.caps)
 
         self.assertEqual(self.caps["XULappId"], self.appinfo["ID"])
         self.assertEqual(self.caps["appBuildId"], self.appinfo["appBuildID"])
-        self.assertEqual(self.caps["version"], self.appinfo["version"])
 
     def test_we_can_pass_in_capabilities_on_session_start(self):
         self.marionette.delete_session()
         capabilities = {"desiredCapabilities": {"somethingAwesome": "cake"}}
         self.marionette.start_session(capabilities)
         caps = self.marionette.session_capabilities
         self.assertIn("somethingAwesome", caps)
 

--- a/testing/marionette/harness/marionette/tests/unit/test_session.py
+++ b/testing/marionette/harness/marionette/tests/unit/test_session.py
@@ -15,23 +15,23 @@ class TestSession(MarionetteTestCase):
         caps = self.marionette.start_session()
 
         # Check that session was created.  This implies the server
         # sent us the sessionId and status fields.
         self.assertIsNotNone(self.marionette.session)
 
         # Required capabilities mandated by WebDriver spec
         self.assertIn("browserName", caps)
+        self.assertIn("browserVersion", caps)
         self.assertIn("platformName", caps)
         self.assertIn("platformVersion", caps)
 
         # Optional capabilities we want Marionette to support
         self.assertIn("rotatable", caps)
         self.assertIn("takesScreenshot", caps)
-        self.assertIn("version", caps)
 
     def test_we_can_get_the_session_id(self):
         # Sends newSession
         self.marionette.start_session()
 
         self.assertTrue(self.marionette.session_id is not None)
         self.assertTrue(isinstance(self.marionette.session_id, unicode))