--- a/testing/marionette/harness/marionette_harness/tests/unit/test_capabilities.py
+++ b/testing/marionette/harness/marionette_harness/tests/unit/test_capabilities.py
@@ -2,21 +2,16 @@
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 from __future__ import absolute_import, print_function
 
 from marionette_driver.errors import SessionNotCreatedException
 from marionette_harness import MarionetteTestCase
 
-# Unlike python 3, python 2 doesn't have a proper implementation of realpath or
-# samefile for Windows. However this function, which does exactly what we want,
-# was added to python 2 to fix an issue with tcl installations and symlinks.
-from FixTk import convert_path
-
 
 class TestCapabilities(MarionetteTestCase):
 
     def setUp(self):
         super(TestCapabilities, self).setUp()
         self.caps = self.marionette.session_capabilities
         with self.marionette.using_context("chrome"):
             self.appinfo = self.marionette.execute_script("""
@@ -57,19 +52,19 @@ class TestCapabilities(MarionetteTestCas
         self.assertEqual(self.caps["moz:processID"], self.appinfo["processID"])
         self.assertEqual(self.marionette.process_id, self.appinfo["processID"])
 
         self.assertIn("moz:profile", self.caps)
         if self.marionette.instance is not None:
             if self.caps["browserName"] == "fennec":
                 current_profile = self.marionette.instance.runner.device.app_ctx.remote_profile
             else:
-                current_profile = convert_path(self.marionette.instance.runner.profile.profile)
-            self.assertEqual(convert_path(str(self.caps["moz:profile"])), current_profile)
-            self.assertEqual(convert_path(str(self.marionette.profile)), current_profile)
+                current_profile = self.marionette.profile_path
+            # Bug 1438461 - mozprofile uses lower-case letters even on case-sensitive filesystems
+            self.assertEqual(self.caps["moz:profile"].lower(), current_profile.lower())
 
         self.assertIn("moz:accessibilityChecks", self.caps)
         self.assertFalse(self.caps["moz:accessibilityChecks"])
 
         self.assertIn("moz:useNonSpecCompliantPointerOrigin", self.caps)
         self.assertFalse(self.caps["moz:useNonSpecCompliantPointerOrigin"])
 
         self.assertIn("moz:webdriverClick", self.caps)