diff --git a/ptvsd/wrapper.py b/ptvsd/wrapper.py
index 86ef535c..080af26c 100644
--- a/ptvsd/wrapper.py
+++ b/ptvsd/wrapper.py
@@ -1397,13 +1397,13 @@ class VSCodeMessageProcessor(VSCLifecycleMsgProcessor):
             vendored_pydevd = os.path.sep + \
                               os.path.join('ptvsd', '_vendored', 'pydevd')
             ptvsd_path = os.path.sep + 'ptvsd'
+            site_path = os.path.sep + 'site-packages'
 
             project_dirs = []
             for path in sys.path + [os.getcwd()]:
                 is_stdlib = False
                 norm_path = os.path.normcase(path)
-                if path.endswith(ptvsd_path) or \
-                   path.endswith(vendored_pydevd):
+                if path.endswith((ptvsd_path, vendored_pydevd, site_path)):
                     is_stdlib = True
                 else:
                     for prefix in STDLIB_PATH_PREFIXES:
@@ -2301,7 +2301,8 @@ class VSCodeMessageProcessor(VSCLifecycleMsgProcessor):
         xframe = xframes[0]
         filepath = unquote(xframe['file'])
         if reason in STEP_REASONS or reason in EXCEPTION_REASONS:
-            if not self._should_debug(filepath):
+            if self.internals_filter.is_internal_path(filepath) or \
+                not self._should_debug(filepath):
                 self.pydevd_notify(pydevd_comm.CMD_THREAD_RUN, pyd_tid)
                 return
 
diff --git a/tests/highlevel/__init__.py b/tests/highlevel/__init__.py
index 2ae13a65..5263282a 100644
--- a/tests/highlevel/__init__.py
+++ b/tests/highlevel/__init__.py
@@ -908,7 +908,7 @@ class VSCTest(object):
         expected = list(self.vsc.protocol.parse_each(expected))
         self.assertEqual(received[:-1], expected)
 
-        failure = received[-1]
+        failure = received[-1] if len(received) > 0 else []
         expected = self.vsc.protocol.parse(
             self.fix.vsc_msgs.new_failure(req, failure.message))
         self.assertEqual(failure, expected)
diff --git a/tests/highlevel/test_lifecycle.py b/tests/highlevel/test_lifecycle.py
index 1fc7f86d..e3b37960 100644
--- a/tests/highlevel/test_lifecycle.py
+++ b/tests/highlevel/test_lifecycle.py
@@ -30,13 +30,13 @@ def _get_project_dirs():
     vendored_pydevd = os.path.sep + \
                       os.path.join('ptvsd', '_vendored', 'pydevd')
     ptvsd_path = os.path.sep + 'ptvsd'
+    site_path = os.path.sep + 'site-packages'
 
     project_dirs = []
     for path in sys.path + [os.getcwd()]:
         is_stdlib = False
         norm_path = os.path.normcase(path)
-        if path.endswith(ptvsd_path) or \
-            path.endswith(vendored_pydevd):
+        if path.endswith((ptvsd_path, vendored_pydevd, site_path)):
             is_stdlib = True
         else:
             for prefix in ptvsd.wrapper.STDLIB_PATH_PREFIXES:
diff --git a/tests/system_tests/test_web_frameworks.py b/tests/system_tests/test_web_frameworks.py
index afd68010..8c509a1f 100644
--- a/tests/system_tests/test_web_frameworks.py
+++ b/tests/system_tests/test_web_frameworks.py
@@ -378,7 +378,7 @@ class FlaskLaunchFileTests(WebFrameworkTests):
                     'FLASK_ENV': 'development',
                     'FLASK_DEBUG': '0',
                     'LC_ALL': 'C.UTF-8',
-                    'LANG': 'C.UTF-8'
+                    'LANG': 'C.UTF-8',
                 },
                 cwd=cwd),
             framework='Jinja',
@@ -399,7 +399,7 @@ class FlaskLaunchFileTests(WebFrameworkTests):
                     'FLASK_ENV': 'development',
                     'FLASK_DEBUG': '0',
                     'LC_ALL': 'C.UTF-8',
-                    'LANG': 'C.UTF-8'
+                    'LANG': 'C.UTF-8',
                 },
                 cwd=cwd),
             framework='Jinja',
@@ -418,7 +418,7 @@ class FlaskLaunchFileTests(WebFrameworkTests):
                     'FLASK_ENV': 'development',
                     'FLASK_DEBUG': '0',
                     'LC_ALL': 'C.UTF-8',
-                    'LANG': 'C.UTF-8'
+                    'LANG': 'C.UTF-8',
                 },
                 cwd=cwd), 'Jinja', filename)
 
@@ -434,7 +434,7 @@ class FlaskLaunchFileTests(WebFrameworkTests):
                     'FLASK_ENV': 'development',
                     'FLASK_DEBUG': '0',
                     'LC_ALL': 'C.UTF-8',
-                    'LANG': 'C.UTF-8'
+                    'LANG': 'C.UTF-8',
                 },
                 cwd=cwd), 'Jinja', filename)