deleted file mode 100644
--- a/gecko.log
+++ /dev/null
@@ -1,103 +0,0 @@
-1470307173716	Marionette	INFO	Listening on port 2828
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_l10n.py:test_dtd_entity_chrome
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_l10n.py:test_dtd_entity_chrome
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_l10n.py:test_dtd_entity_content
-ATTENTION: default value of option force_s3tc_enable overridden by environment.
-WebGL(0x7fc9ceb90800)::ForceLoseContext
-WebGL(0x7fc9b835a800)::ForceLoseContext
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_l10n.py:test_dtd_entity_content
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_l10n.py:test_properties
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_l10n.py:test_properties
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_places.py:test_bookmarks
-
-(firefox:3146): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'g_type_parent (interface_type) == G_TYPE_INTERFACE' failed
-
-(firefox:3146): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'g_type_parent (interface_type) == G_TYPE_INTERFACE' failed
-
-(firefox:3146): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'g_type_parent (interface_type) == G_TYPE_INTERFACE' failed
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_places.py:test_bookmarks
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_places.py:test_history
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_places.py:test_history
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_places.py:test_plugins
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_places.py:test_plugins
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_get_pref
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_get_pref
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_reset_pref
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_reset_pref
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_restore_all_prefs
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_restore_all_prefs
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_restore_pref
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_restore_pref
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_set_pref_casted_values
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_set_pref_casted_values
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_set_pref_invalid
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_set_pref_invalid
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_set_pref_new_preference
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_set_pref_new_preference
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_set_pref_new_values
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_prefs.py:test_set_pref_new_values
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_security.py:test_get_address_from_certificate
-JavaScript error: chrome://marionette/content/listener.js, line 1017: NS_ERROR_FAILURE: Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIWebProgress.removeProgressListener]
-JavaScript error: chrome://marionette/content/listener.js, line 1017: NS_ERROR_FAILURE: Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIWebProgress.removeProgressListener]
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_security.py:test_get_address_from_certificate
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_security.py:test_get_certificate
-JavaScript error: chrome://marionette/content/listener.js, line 1017: NS_ERROR_FAILURE: Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIWebProgress.removeProgressListener]
-1470307248863	addons.productaddons	WARN	Failed downloading XML, status: 0, reason: error
-1470307255382	Marionette	INFO	Listening on port 2828
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_mar_channels_add_channels
-JavaScript error: file:///home/envy/Documents/mozilla-central/obj-x86_64-pc-linux-gnu/dist/bin/components/nsINIProcessor.js, line 146: NS_ERROR_FILE_ACCESS_DENIED: Component returned failure code: 0x80520015 (NS_ERROR_FILE_ACCESS_DENIED) [nsIFileOutputStream.init]
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_mar_channels_channels
-JavaScript error: file:///home/envy/Documents/mozilla-central/obj-x86_64-pc-linux-gnu/dist/bin/components/nsINIProcessor.js, line 146: NS_ERROR_FILE_ACCESS_DENIED: Component returned failure code: 0x80520015 (NS_ERROR_FILE_ACCESS_DENIED) [nsIFileOutputStream.init]
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_mar_channels_remove_channels
-JavaScript error: file:///home/envy/Documents/mozilla-central/obj-x86_64-pc-linux-gnu/dist/bin/components/nsINIProcessor.js, line 146: NS_ERROR_FILE_ACCESS_DENIED: Component returned failure code: 0x80520015 (NS_ERROR_FILE_ACCESS_DENIED) [nsIFileOutputStream.init]
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_mar_channels_set_channels
-JavaScript error: file:///home/envy/Documents/mozilla-central/obj-x86_64-pc-linux-gnu/dist/bin/components/nsINIProcessor.js, line 146: NS_ERROR_FILE_ACCESS_DENIED: Component returned failure code: 0x80520015 (NS_ERROR_FILE_ACCESS_DENIED) [nsIFileOutputStream.init]
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_abi
-JavaScript error: file:///home/envy/Documents/mozilla-central/obj-x86_64-pc-linux-gnu/dist/bin/components/nsINIProcessor.js, line 146: NS_ERROR_FILE_ACCESS_DENIED: Component returned failure code: 0x80520015 (NS_ERROR_FILE_ACCESS_DENIED) [nsIFileOutputStream.init]
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_allowed
-JavaScript error: file:///home/envy/Documents/mozilla-central/obj-x86_64-pc-linux-gnu/dist/bin/components/nsINIProcessor.js, line 146: NS_ERROR_FILE_ACCESS_DENIED: Component returned failure code: 0x80520015 (NS_ERROR_FILE_ACCESS_DENIED) [nsIFileOutputStream.init]
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_build_info
-JavaScript error: file:///home/envy/Documents/mozilla-central/obj-x86_64-pc-linux-gnu/dist/bin/components/nsINIProcessor.js, line 146: NS_ERROR_FILE_ACCESS_DENIED: Component returned failure code: 0x80520015 (NS_ERROR_FILE_ACCESS_DENIED) [nsIFileOutputStream.init]
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_force_fallback
-JavaScript error: file:///home/envy/Documents/mozilla-central/obj-x86_64-pc-linux-gnu/dist/bin/components/nsINIProcessor.js, line 146: NS_ERROR_FILE_ACCESS_DENIED: Component returned failure code: 0x80520015 (NS_ERROR_FILE_ACCESS_DENIED) [nsIFileOutputStream.init]
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_get_update_url
-JavaScript error: file:///home/envy/Documents/mozilla-central/obj-x86_64-pc-linux-gnu/dist/bin/components/nsINIProcessor.js, line 146: NS_ERROR_FILE_ACCESS_DENIED: Component returned failure code: 0x80520015 (NS_ERROR_FILE_ACCESS_DENIED) [nsIFileOutputStream.init]
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_os_version
-JavaScript error: file:///home/envy/Documents/mozilla-central/obj-x86_64-pc-linux-gnu/dist/bin/components/nsINIProcessor.js, line 146: NS_ERROR_FILE_ACCESS_DENIED: Component returned failure code: 0x80520015 (NS_ERROR_FILE_ACCESS_DENIED) [nsIFileOutputStream.init]
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_staging_directory
-JavaScript error: file:///home/envy/Documents/mozilla-central/obj-x86_64-pc-linux-gnu/dist/bin/components/nsINIProcessor.js, line 146: NS_ERROR_FILE_ACCESS_DENIED: Component returned failure code: 0x80520015 (NS_ERROR_FILE_ACCESS_DENIED) [nsIFileOutputStream.init]
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_update_channel_channel
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_update_channel_default_channel
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_software_update.py:test_update_channel_set_default_channel
-1470307267490	Marionette	INFO	Listening on port 2828
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_utils.py:test_sanitize_history
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_utils.py:test_sanitize_history
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_about_window.py:test_basic
-
-(firefox:3639): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'g_type_parent (interface_type) == G_TYPE_INTERFACE' failed
-
-(firefox:3639): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'g_type_parent (interface_type) == G_TYPE_INTERFACE' failed
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_about_window.py:test_basic
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_about_window.py:test_elements
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_about_window.py:test_elements
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_about_window.py:test_open_window
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_about_window.py:test_open_window
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_menubar.py:test_click_item_in_menubar
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_menubar.py:test_click_item_in_menubar
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_menubar.py:test_click_non_existent_menu_and_item
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_menubar.py:test_click_non_existent_menu_and_item
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_notifications.py:test_addon_install_failed_notification
-1470307280803	addons.xpi	WARN	Add-on restartless-eula@mozqa.com not signed.
-1470307280804	addons.xpi	WARN	Download of http://127.0.0.1:39570/addons/extensions/restartless_addon_unsigned.xpi failed: signature is required but missing
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_notifications.py:test_addon_install_failed_notification
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_notifications.py:test_notification_with_origin
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_notifications.py:test_notification_with_origin
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_notifications.py:test_open_close_notification
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_notifications.py:test_open_close_notification
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_notifications.py:test_wait_for_no_notification_timeout
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_notifications.py:test_wait_for_no_notification_timeout
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_notifications.py:test_wait_for_notification_timeout
-
-(firefox:3639): GLib-GObject-CRITICAL **: g_type_add_interface_static: assertion 'g_type_parent (interface_type) == G_TYPE_INTERFACE' failed
-MARIONETTE LOG: INFO: TEST-END: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_notifications.py:test_wait_for_notification_timeout
-MARIONETTE LOG: INFO: TEST-START: /home/envy/Documents/mozilla-central/testing/firefox-ui/tests/puppeteer/test_notifications.py:test_wait_for_specific_notification_timeout

new file mode 100644
--- /dev/null
+++ b/testing/firefox-ui/.flake8
@@ -0,0 +1,3 @@
+[flake8]
+max-line-length = 99
+exclude = __init__.py,

--- a/testing/firefox-ui/harness/firefox_ui_harness/__init__.py
+++ b/testing/firefox-ui/harness/firefox_ui_harness/__init__.py
@@ -1,8 +1,8 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # 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/.
 
 __version__ = '1.4.0'
 
-import cli_functional # noqa
-import cli_update  # noqa
+import cli_functional 
+import cli_update  

--- a/testing/firefox-ui/harness/firefox_ui_harness/arguments/__init__.py
+++ b/testing/firefox-ui/harness/firefox_ui_harness/arguments/__init__.py
@@ -1,6 +1,6 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # 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 firefox_ui_harness.arguments.base import FirefoxUIArguments  # noqa
-from firefox_ui_harness.arguments.update import UpdateArguments  # noqa
+from firefox_ui_harness.arguments.base import FirefoxUIArguments  
+from firefox_ui_harness.arguments.update import UpdateArguments  

--- a/testing/firefox-ui/harness/firefox_ui_harness/runners/__init__.py
+++ b/testing/firefox-ui/harness/firefox_ui_harness/runners/__init__.py
@@ -1,6 +1,6 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # 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 firefox_ui_harness.runners.base import FirefoxUITestRunner # noqa
-from firefox_ui_harness.runners.update import UpdateTestRunner # noqa
+from firefox_ui_harness.runners.base import FirefoxUITestRunner
+from firefox_ui_harness.runners.update import UpdateTestRunner 

--- a/testing/firefox-ui/tests/functional/security/test_mixed_content_page.py
+++ b/testing/firefox-ui/tests/functional/security/test_mixed_content_page.py
@@ -1,14 +1,12 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # 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 marionette_driver import Wait # noqa
-
 from firefox_ui_harness.testcases import FirefoxTestCase
 
 
 class TestMixedContentPage(FirefoxTestCase):
     def setUp(self):
         FirefoxTestCase.setUp(self)
 
         self.locationbar = self.browser.navbar.locationbar

--- a/testing/firefox-ui/tests/puppeteer/test_menubar.py
+++ b/testing/firefox-ui/tests/puppeteer/test_menubar.py
@@ -8,18 +8,16 @@ from firefox_ui_harness.testcases import
 
 
 class TestMenuBar(FirefoxTestCase):
 
     def setUp(self):
         FirefoxTestCase.setUp(self)
 
     def test_click_item_in_menubar(self):
-        num_tabs = len(self.browser.tabbar.tabs) # noqa
-
         def opener(_):
             self.browser.menubar.select_by_id('file-menu',
                                               'menu_newNavigatorTab')
 
         self.browser.tabbar.open_tab(trigger=opener)
 
         self.browser.tabbar.tabs[-1].close()
 

--- a/testing/firefox-ui/tests/puppeteer/test_page_info_window.py
+++ b/testing/firefox-ui/tests/puppeteer/test_page_info_window.py
@@ -1,13 +1,12 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # 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 marionette_driver import By # noqa
 from firefox_ui_harness.testcases import FirefoxTestCase
 
 
 class TestPageInfoWindow(FirefoxTestCase):
 
     def tearDown(self):
         try:
             self.windows.close_all([self.browser])

--- a/testing/firefox-ui/tests/puppeteer/test_windows.py
+++ b/testing/firefox-ui/tests/puppeteer/test_windows.py
@@ -1,14 +1,14 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # 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 marionette_driver import By, Wait
-from marionette_driver.errors import NoSuchWindowException, TimeoutException  # noqa
+from marionette_driver.errors import NoSuchWindowException
 
 import firefox_puppeteer.errors as errors
 
 from firefox_puppeteer.ui.windows import BaseWindow
 from firefox_ui_harness.testcases import FirefoxTestCase
 
 
 class TestWindows(FirefoxTestCase):

new file mode 100644
--- /dev/null
+++ b/testing/puppeteer/.flake8
@@ -0,0 +1,3 @@
+[flake8]
+max-line-length = 99
+exclude = __init__.py,

--- a/testing/puppeteer/firefox/firefox_puppeteer/__init__.py
+++ b/testing/puppeteer/firefox/firefox_puppeteer/__init__.py
@@ -1,13 +1,13 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # 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/.
 
-import os  # noqa
+import os
 
 from marionette_driver.marionette import HTMLElement
 
 from decorators import use_class_as_property
 
 
 __version__ = '50.0.0'
 

--- a/testing/puppeteer/firefox/firefox_puppeteer/testcases/__init__.py
+++ b/testing/puppeteer/firefox/firefox_puppeteer/testcases/__init__.py
@@ -1,5 +1,5 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # 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 firefox_puppeteer.testcases.base import BaseFirefoxTestCase  # noqa
+from firefox_puppeteer.testcases.base import BaseFirefoxTestCase

--- a/testing/puppeteer/firefox/firefox_puppeteer/ui/browser/window.py
+++ b/testing/puppeteer/firefox/firefox_puppeteer/ui/browser/window.py
@@ -1,34 +1,26 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # 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/.
 
-import firefox_puppeteer.errors as errors  # noqa
-
 from marionette_driver import By, Wait
-from marionette_driver.errors import NoSuchElementException, NoSuchWindowException  # noqa
-from marionette_driver.keys import Keys  # noqa
-
-from firefox_puppeteer.api.l10n import L10n  # noqa
-from firefox_puppeteer.api.prefs import Preferences  # noqa
-from firefox_puppeteer.decorators import use_class_as_property  # noqa
+from marionette_driver.errors import NoSuchElementException
 from firefox_puppeteer.ui.about_window.window import AboutWindow
 from firefox_puppeteer.ui.browser.notifications import (
     AddOnInstallBlockedNotification,
     AddOnInstallConfirmationNotification,
     AddOnInstallCompleteNotification,
     AddOnInstallFailedNotification,
     AddOnProgressNotification,
     BaseNotification)
 from firefox_puppeteer.ui.browser.tabbar import TabBar
 from firefox_puppeteer.ui.browser.toolbars import NavBar
 from firefox_puppeteer.ui.pageinfo.window import PageInfoWindow
 from firefox_puppeteer.ui.windows import BaseWindow, Windows
-# import firefox_puppeteer.errors as errors
 
 
 class BrowserWindow(BaseWindow):
     """Representation of a browser window."""
 
     window_type = 'navigator:browser'
 
     dtds = [

--- a/testing/puppeteer/firefox/firefox_puppeteer/ui/update_wizard/__init__.py
+++ b/testing/puppeteer/firefox/firefox_puppeteer/ui/update_wizard/__init__.py
@@ -1,5 +1,5 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # 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 dialog import UpdateWizardDialog  # noqa
+from dialog import UpdateWizardDialog

--- a/tools/lint/flake8.lint
+++ b/tools/lint/flake8.lint
@@ -118,19 +118,19 @@ def lint(files, **lintargs):
     return results
 
 
 LINTER = {
     'name': "flake8",
     'description': "Python linter",
     'include': [
         'python/mozlint',
-        'tools/lint',
         'taskcluster',
+        'testing/firefox-ui',
         'testing/marionette/client',
+        'testing/puppeteer',
         'testing/talos/',
-        'testing/firefox-ui',
-        'testing/puppeteer',
+        'tools/lint',
     ],
     'exclude': [],
     'type': 'external',
     'payload': lint,
 }